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Madhoo, Jitesh. "Continuous low dose rate irradiation of the rat brain." Doctoral thesis, University of Cape Town, 1999. http://hdl.handle.net/11427/26785.
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The reported median survival time for patients who are diagnosed with high grade astrocytomas and who undergo postoperative radiotherapy is of the order of 24 to 40 weeks. The course of radiotherapy administered to these patients takes up a considerable portion of their expected survival time. Therefore, any means of reducing the treatment time may contribute to an enhanced quality of life for these patients. A potentially useful method for the reduction of the treatment time may be achieved with the use of continuous low dose rate external beam radiotherapy, where the treatment is administered over a 12 to 24 hour period. A relationship between fractionated and continuous low dose rate irradiation has been reported for skin, however, no such relationship has been reported for the brain. Low dose rate protocols that are equivalent in effect to fractionated (conventional) protocols can be derived using the linear quadratic theory, provided that quantitative radiobiological data for normal tissue (brain) is known. Thus, the aim of the current study is to test the radiation tolerance of the rat brain to low dose rate and fractionated radiation in order to establish the values for the parameters of the linear quadratic model.
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Amorim, João Paulo de Arruda 1981. "Caracterização do comportamento materno e suas implicações no desenvovimento fisico,na função reprodutiva e no perfil hormonal da prole feminina de ratas UChA e UChB (consumidoras voluntárias de etanol a 10%)." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317536.
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Orientadores: Francisco Eduardo Martinez, Wilson de Mello JuniorTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Estudos realizados com mães dependentes de etanol demonstraram que elas apresentam maior dificuldade em cuidar de suas crianças, quando comparadas às mães não dependentes, evidenciando um distúrbio no comportamento materno durante o período pós-natal, que corresponde ao período onde as primeiras ligações sociais do animal são formadas e o organismo está muito sensível aos efeitos de estímulos ambientais. Vários estudos têm documentado as conseqüências do uso de etanol durante a gestação para a saúde do infante, porém pouca atenção tem sido dada à relação materno-infantil em mulheres alcoólicas durante o período pós-natal e as consequências dessa relação para prole feminina na vida adulta. O presente trabalho teve o objetivo de caracterizar o comportamento materno das ratas da variedade consumidora de etanol (UChA e UChB) e verificar as influências da variação do comportamento materno no desenvolvimento físico, na função reprodutiva e no status hormonal da prole feminina. O comportamento foi avaliado observando os seguintes parâmetros: carregar, lamber, amamentar com o dorso arcado e lamber, amamentar com o dorso arcado, amamentar passivamente e não contato com a prole. A avaliação do desenvolvimento físico da prole feminina considerou o dia do nascimento dos pêlos, da abertura dos olhos e do descolamento de orelhas. Para avaliar o desenvolvimento sexual inicial foram analisados os dias da abertura vaginal e idade do primeiro e segundo estro. A função reprodutiva foi avaliada pela regularidade de ciclo estral, pela expressão dos receptores AR, ER-? e ER-? no ovário e pelo perfil hormonal da prole feminina (níveis plasmáticos de FSH, LH, 17?-estradiol, progesterona e corticosterona). As fêmeas UChA apresentaram maiores frequências dos comportamentos de carregar, de lamber/limpar e de amamentar os filhotes. Mães muito cuidadosas apresentaram concentrações elevadas de corticosterona e 17?-estradiol. A prole UChA apresentou maior ganho de peso corporal, aceleração da abertura dos olhos, da abertura vaginal, da instalação da puberdade e sincronização do ciclo estral. A prole feminina que recebeu baixo cuidado materno (UChB) revelou maior duração do ciclo estral, aumento das concentrações de corticosterona e 17?-estradiol e de seus receptores ovarianos (ER-? e ER-?), maior peso dos ovários, maior número de folículos primordiais, antrais e maduros e mais imunomarcações positivas do Ki67 nos folículos ovarianos. Concluímos que a variedade de ratas UChB, apresenta acentuada variação do comportamento materno, sendo classificada como mãe pouco cuidadosa e essa variação do cuidado materno afeta diretamente o desenvolvimento físico, a instalação da puberdade, os níveis hormonais, desregula o ciclo estral e a foliculogênese e regula diferencialmente a expressão dos receptores ER-? e ER-? nos ovários de ratas adultas
Abstract: Studies focused on drug-dependent mothers (mainly ethanol-dependent mothers) have demonstrated that there is an enormous difference in the care of their children compared to non-dependent mothers, showing an disorder in maternal behavior during the postnatal period, which corresponds to the period where the first social bonds are formed and the animal's organism is very sensible to the effects of environmental stimuli. Various studies have documented the consequences of ethanol use during pregnancy for the health of the infant, but little attention has been given to the mother-child relationship in alcoholic female during the postnatal period and the consequences of this relationship to female offspring in adulthood. The aim of the present work is to evaluate maternal care in ethanol-preferring rats (UChA and UChB) and its effects on physical development, in sexual function and in status hormones in female offspring. The behavior was evaluated by observing the following parameters: carry, licking/grooming, arched-back nursing and licking/grooming, arched-back nursing, passive nursing, contact and not with the pups. The evaluation of the physical development of the female offspring considered the day of birth of hair, eye opening and detached ears. To evaluate the early sexual development were analyzed days of vaginal opening and age of first and second estrous. The reproductive function was evaluated by the regularity of the estrous cycle, the expression of receptors AR, ER-? and ER-? in the ovary and the hormonal status of female offspring (plasma levels of FSH, LH, 17?-estradiol, progesterone and corticosterone). UChA mothers showed higher frequencies of carrying, licking/grooming and nursing the pups. Mothers high care evidencing the highest plasma corticosterone levels and 17?-estradiol. The UChA offspring showed greater body weight gain, accelerated eye opening, vaginal opening, the installation and synchronization of estrous cycle. The female offspring who received low maternal care (UChB) showed an increase of the estrous cycle, concentrations of corticosterone and 17?-estradiol and ovarian receptors (ER-? and ER-?, higher ovarian weight and increased number of primordial, antral and mature follicles and higher Immunoreactivity for Ki-67 in the ovarian follicles. We conclude that UChB rats show marked variations in maternal care, being classified as low maternal care and the variation of maternal care directly affects the physical, the installation of puberty, hormone levels, deregulate the estrous cycle and folliculogenesis and differentially regulates the expression of receptors ER-? and ER-? in the ovaries of adult rats
Doutorado
Anatomia
Doutor em Biologia Celular e Estrutural
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Lewis, S. J. "Studies in catch-up growth in the rat skeleton." Thesis, Bucks New University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382473.
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Sadi, Gokhan. "Antioxidant Enzyme Activities In Rat Liver Tissues Of Diabetic Rats." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/2/12605254/index.pdf.
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Free radicals are the compounds having one or more unpaired electrons in their outer orbital and this unpaired electron make these compounds very reactive. Especially as their concentration increases, they initiate a chain oxidation reaction of lipids, proteins and nucleic acids. The condition, in which the production of free radicals exceeds their elimination or tissue defense mechanism decrease against them or both occur together, is called oxidative stress. In diabetes mellitus which is a glucose metabolism disorder, there occurs excessive non-enzymatic protein oxidation, glucose autoxidation and enhanced activity of polyol pathway enzymes, which are the possible sources of the oxidative stress in this disease.
In this study, the conditions of the activity measurements of major antioxidant enzymes, namely superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), glutathione peroxidase (GPx, 1.11.1.9) and glutathione S-transferase (GST, EC 2.5.1.18) were studied and the optimum conditions (pH, temperature and substrate concentrations) for each assay were determined.
Further objectives of the study were to characterize the enzymatic antioxidant systems (catalase, superoxide dismutase, glutathione peroxidase and glutathione S-transferase), tissue oxidation status (concentrations of TBARS, protein carbonylation, and lipid/protein ratios) and nonenzymatic antioxidant (reduced glutathione) levels of the diabetic rat liver tissues.
According to our results, the hepatic SOD and GPx activities significantly increased whereas CAT activity markedly decreased in diabetic rats compared to control group. Also, GST activities did not change in diabetes. As a result of oxidative stress, TBARS concentration, lipid/protein ratios and protein carbonylation increased and GSH levels decreased in diabetic rats compared to control rats. This increase in tissue damage, in spite of the increase in antioxidant enzyme activities, could have been due to the overproduction of reactive oxygen species that exceeded the capacity of the antioxidant enzymes during the eight week of diabetes.
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Edlund, G. L. "Lactate and pyruvate transport in rat erythrocytes and rat hepatocytes." Thesis, University of Bristol, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375019.
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Costa, Rafaela 1984. "Efeitos da estimulação tatil em ratos adultos jovens, submetidos ou não ao modelo de estresse cronico." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288840.
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Orientador: Fernanda Klein MarcondesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Problemas emocionais como ansiedade e depressão, relacionados ao estresse, estão cada vez mais presentes na sociedade moderna, e o suporte social, mais especificadamente suporte familiar, pode exercer um importante papel em atenuar os efeitos de diversos estressores. Em modelos animais o enriquecimento ambiental tem sido utilizado para melhora do bem estar animal. O objetivo deste estudo foi avaliar os efeitos do enriquecimento ambiental por meio da estimulação tátil em ratos submetidos ou não a estresse crônico. No Capítulo I, foi evidenciado que a estimulação tátil diminuiu a ansiedade e aumentou as respostas indicadoras de aprendizado e memória em ratos jovem-adultos. No Capítulo II, foram avaliados os efeitos do estresse crônico moderado e imprevisível e da estimulação tátil sobre respostas comportamentais (ansiedade, anedonia, aprendizado e memória) e sobre o perfil lipídico. O estresse aumentou a secreção de corticosterona avaliada quinze dias após o fim do estresse; induziu anedonia evidenciada pela diminuição da preferência pela sacarose 1%; aumentou a atividade locomotora; teve efeito negativo sobre o aprendizado e memória; e aumentou a concentração sérica de triglicerídeos, colesterol total e lipoproteína de baixa densidade (LDL). A manipulação diminuiu a ansiedade em animais submetidos ou não ao estresse crônico; diminuiu a secreção de corticosterona induzida pelo estresse e cancelou a redução do aprendizado e retenção de memória induzida pelo estresse crônico. Os resultados obtidos mostram que a estimulação tátil de ratos adultos jovens produziu efeitos comportamentais positivos que podem melhorar o bem-estar animal e diminuir efeitos deletérios induzidos pelo estresse crônico.
Abstract: Emotional problems such as stress related anxiety and depression, are becoming increasingly present in modern society, and social support, more specifically familiar support, can play an important role in attenuating the effects of various stressors. In animal models environmental enrichment has been used to improve animal welfare. The aim of this study was to evaluate the effects of environmental enrichment by handling, in rats submitted and those not submitted to chronic stress. In chapter 1 it was shown that handling diminished anxiety, and enhanced learning abilities and memory indicating response in young-adult rats. In chapter 2 the effects of handling on behavioral (anxiety, ahnedonia, learning and memory) and metabolic responses induced by chronic mild unpredictable stress. Whereas stress raised the corticosterone secretion evaluated fifteen days after the end of stress; induced ahnedonia evidenced by a 1% decrease in sucrose preference; increased locomotor activity; had negative effects on learning and memory; and raised the serum concentration of triglycerides, total cholesterol and low density lipoprotein (LDL). Handling reduced the anxiety in animals both when they were and were not submitted to chronic stress; diminished the corticosterone secretion induced by the stress and cancelled the reduction of learning and memory retention induced by the chronic stress. The results obtained showed that the handling of young-adult rats produced positive behavioral effects capable of improving the animal's welfare and diminishing the deleterious effects induced by chronic stress.
Mestrado
Fisiologia Oral
Mestre em Odontologia
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Bobrov, Evgeny. "Rat social touch." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2014. http://dx.doi.org/10.18452/17036.
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Ratten verwenden Schnurrhaare (Vibrissen) zur Berührungswahrnehmung, und die Leitungsbahn von den Vibrissen zum primären somatosensorischen Areal (Barrel Cortex, BC) ist gut untersucht. Ratten zeigen auch vielfältiges Sozialverhalten, u.a. Berührung von Artgenossen mit ihren Vibrissen. Es ist jedoch unbekannt, wie diese sozialen Berührungssignale im Gehirn repräsentiert sind. Deshalb hatte die vorliegende Studie zum Ziel, die neuronale Repräsentation von sozialen Berührungen im BC zu untersuchen und mit anderer somatosensorischer Stimulation zu vergleichen. Mit extrazellulären Einzelzellableitungen in sich frei bewegenden Ratten habe ich gezeigt, dass die Aktivität eines Großteils von Neuronen im BC durch soziale Berührungen moduliert wird. Antworten waren meist erregend und Feuerraten während sozialer Interaktionen unterschieden sich zwischen kortikalen Schichten. Ratten bevorzugten Interaktionen mit Artgenossen gegenüber unbelebten Stimuli. Auch die Berührungsstrategien unterschieden sich, dabei wurden Objekte mit regelmäßigeren Bewegungen abgetastet, und die Vibrissen weiter vorgestreckt. Neuronale Antworten unterschieden sich ebenso, mit leicht aber konsistent schwächeren Antworten auf Objekte. Interessanterweise habe ich geschlechtsspezifische Unterschiede in neuronalen Antworten beobachtet. Der ausgeprägteste war die stärkere Modulation regulär-feuernder (RF) Zellen in Männchen während sozialer Berührungen. Dieser Unterschied konnte nicht mit sozialem Berührungsverhalten erklärt werden, was eventuell auf eine neurale Grundlage dieser Differenz hindeutet. Zudem feuerten RF-Zellen von Weibchen deutlich seltener, wenn das Weibchen im Östrus war. Zusammenfassend ist dies die erste Studie, die soziale Signale in einem primären sensorischen Areal bei sich frei bewegenden Tieren auf zellulärer Ebene untersuchte. Sie legt nahe, dass die Repräsentationen sensorischer Hirnrinde weniger stimulusabhängig und stärker top-down-moduliert sein könnten, als zuvor angenommen.Rats use their stiff facial hairs (whiskers) for somatosensation, and the pathway from the whiskers to the primary somatosensory cortex (barrel cortex, BC) is well known. Rats also show diverse social behaviors, including touch of conspecifics with their whiskers. The representation of these social touch signals in the brain is however unknown. Thus, the present study aimed at characterizing the neuronal representation of social touch signals in BC and comparing them with non-social somatosensory stimulation. Using extracellular single-cell recordings in freely-moving rats, I could show that the activity of a large fraction of BC neurons is modulated by social touch. Responses were typically excitatory and the pattern of firing rates during interactions differed between cortical layers. Rats preferred interactions with alive conspecifics over inanimate stimuli. Whisking strategies also differed in that inanimate stimuli were whisked at with more regular movements from more protracted set angles. Neuronal responses were also different, such that objects elicited slightly but consistently weaker responses than alive rats. Interestingly, I observed sex-specific differences in neuronal responses. Prominently, there was stronger modulation by social touch in regular-spikers (RS) recorded from males. This could not be explained by behavioral measures, possibly indicating a neural origin of this difference. Further, RS from females fired much more weakly when females were in estrus. In summary, this is the first study that investigated social signals in a primary sensory area of freely-moving animals at the cellular level. It suggests that representations in sensory cortices might be less stimulus-driven and more top-down modulated than previously thought.
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HASSANI, OUM KALTOUM. "Controle dopaminergique du noyau sybthalamique chez le rat normal et chez le rat modele de la maladie de parkinson (rats 6-ohda)." Paris 11, 1997. http://www.theses.fr/1997PA112037.
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Un modele d'organisation anatomo-fonctionnelle des ganglions de la base a ete propose par albin et coll. (1989). Selon ce modele, l'expression de l'hypokinesie serait la consequence d'une hyperactivite du noyau subthalamique (nst). Cette derniere resulterait d'un processus de desinhibition mettant en jeu successivement deux voies inhibitrices, la voie striato-pallidale et la voie pallido-subthalamique. Au cours d'une premiere partie de ce travail, nous avons cherche a determiner l'origine de cette hyperactivite. En effectuant des lesions soit de la substance noire pars compacta (rats 6-ohda) soit du globus pallidus soit des deux structures, nous avons pu montrer que l'hyperactivite des neurones subthalamiques provoquee par une lesion de la voie dopaminergique nigrostriatale n'est pas reproduite par une lesion pallidale. Nous avons confirme dans une deuxieme partie, l'existence d'une projection dopaminergique importante vers le nst du rat. L'importance fonctionnelle de cette projection a ete etudiee chez des rats normaux et des rats 6-ohda. Nous avons montre que chez le rat normal la stimulation des recepteurs dopaminergiques d1 et/ou d2 presents dans le nst exercerait un controle inhibiteur sur cette structure. Chez les rats 6-ohda, l'activation des recepteurs d2 produit plutot un renforcement de de cette activite. L'hyperactivite des neurones subthalamiques ne peut etre uniquement la consequence de la depletion dopaminergique. Par ailleurs, chez le rat normal et le rat 6-ohda l'injection systemique d'agonistes dopaminergiques entraine une depression de l'activite des neurones subthalamiques, suggerant ainsi que la dopamine assurerait un controle inhibiteur sur l'activite subthalamique a l'etat normal mais aussi a l'etat parkinsonien. Enfin, chez des rats 6-ohda, l'injection systemique de riluzole entraine une diminution (58,7%) de l'activite des neurones subthalamiques qui atteint une valeur proche de la normale.
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Osypiw, Jacqueline Connett. "Heterogeneity of rat hepatocytes." Thesis, Liverpool John Moores University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261422.
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Sullivan, Lawrence. "Roof Rat Control around Homes and Other Structures." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/146716.
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Mahdouani, Kacem. "Stéroïdes libres urinaires chez le rat normal et le rat génétiquement hypertendu : souche lyonnaise." Lyon 1, 1994. http://www.theses.fr/1994LYO1W331.
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Pascotto, Viviane Mattos [UNESP]. "Influência da mistura de cinco praguicidas em baixas doses sobre o sistema reprodutor de ratas Aprague-Dawley, Wistar e Lewis." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/95894.
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pascotto_vm_me_botfm.pdf: 1234125 bytes, checksum: 1d563b2c7f6645fcba3865762f9c46c7 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O presente projeto objetivou investigar os efeitos da combinação, em baixas doses, de cinco praguicidas (dieldrin, dicofol, endosulfan, diclorvos e permetrina) sobre o sistema reprodutor de ratas Sprague-Dawley, Wistar e Lewis. Ratas de cada linhagem, com seis semanas de idade, foram randomizadas em três grupos: GI: controle negativo; GII: praguicidas adicionados à ração em doses de NOEL (mg/Kg/dia) - diclorvos (0,23), dicofol (0,5), dieldrin (0,025); endosulfan (0,7), permetrina (5); GIII: praguicidas adicionados à ração em doses de LOEL (mg/Kg/dia) - diclorvos (2,3), dicofol (2,1), dieldrin (0,05), endosulfan (3,8), permetrina (25). A eutanásia foi realizada entre a 10ª e a 12ª semana experimental, na fase de estro. Os parâmetros de avaliação foram: peso de fígado, útero e ovários; análise histológica qualitativa de fígado, útero e ovários; morfometria do endométrio; avaliação do ciclo estral; dosagem de LH, FSH e progesterona; e contagem de folículos ovarianos. Animais das três linhagens tratados com a LOEL apresentaram toxicidade sistêmica, evidenciada pela diminuição de peso corpóreo e aumento de peso de fígado. A análise qualitativa de útero e ovários, assim como a avaliação do ciclo estral e níveis hormonais não indicaram sinais de toxicidade reprodutiva exercida pelas misturas. A contagem de folículos ovarianos indicou ausência de resposta dose dependente e alta variabilidade entre os animais de mesmo grupo experimental. Desta forma concluímos que, embora os resultados tenham mostrado diminuição de algumas populações foliculares nas doses de NOEL e LOEL, este parâmetro não pode ser utilizado isoladamente como indicativo de toxicidade reprodutiva. Estes achados remetem à necessidade de maiores estudos para o esclarecimento dos efeitos destes compostos nas populações foliculares
This project aimed to investigate the effects of the combination, in low doses, of five pesticides (dieldrin, dicofol, endosulfan, dichlorvos and permethrin) on the reproductive system of Sprague- Dawley, Wistar and Lewis rats. Six-weeks-old rats from each strain were randomized into three groups: GI: negative control; GII: pesticides added to the feed at NOEL doses (mg/kg/day) - dichlorvos (0.23), dicofol (0.5), dieldrin (0.025), endosulfan (0.7), permethrin (5), GIII: pesticides added to the feed at LOEL doses (mg / kg / day) – dichlorvos (2.3), dicofol (2.1), dieldrin (0.05), endosulfan (3.8), permethrin (25). Euthanasia was performed between the 10th and 12th experimental week, in the estrous stage. The evaluation parameters were: weight of liver, uterus and ovaries; qualitative histological analysis of liver, uterus and ovaries; endometrium morphometry; estrous cycle assessment; dosage of LH, FSH and progesterone; and counting of ovarian follicles. Animals from all three strains showed systemic LOEL toxicity, as evidenced by decreased body weight and increased liver weight. Qualitative analysis of the uterus and ovaries, as well as estrous cycle and hormone levels evaluations indicated no signs of reproductive toxicity exerted by the mixtures. Counting of ovarian follicles indicated lack of dose-dependent response and high variability among animals from the same experimental group. Hence, we concluded that, although our results have shown a decrease of some follicular populations at the NOEL and LOEL doses, this parameter can not be used alone as an indicator of reproductive toxicity. These findings underscore the need for more studies to clarify the effects of these compounds on follicular populations
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Arena, Arielle Cristina. "Parametros reprodutivos masculinos e fertilidade de ratos adultos expostos ao inseticida fenvalerato." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/318043.
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Orientador: Wilma de Grava KempinasTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: O fenvalerato é um inseticida piretróide sintético amplamente utilizado na agricultura para o controle de pragas. Embora seja considerado de baixa toxicidade para os mamíferos, trabalhos têm demonstrado que certos piretróides podem apresentar atividade estrogênica e atuar como desreguladores endócrinos, acarretando disfunções reprodutivas importantes no sexo masculino. Está documentado na literatura que a exposição de ratas prenhes ao fenvalerato reduziu os níveis plasmáticos de testosterona e os pesos da vesícula seminal e do ducto deferente dos filhotes machos na idade adulta, além de alterações no comportamento sexual desses animais. Também foi observado que ratos adultos expostos à formulação de fenvalerato, por inalação, exibiram uma redução significativa no peso dos testículos e na contagem espermática no epidídimo. Até o momento pouco se sabe sobre os mecanismos pelos quais o fenvalerato exerce sua ação na reprodução, assim, o objetivo do presente trabalho foi investigar a atividade estrogênica e os efeitos do inseticida piretróide fenvalerato sobre o sistema reprodutor masculino e fertilidade de ratos machos adultos. Para tanto, ratos machos adultos (90 dias de idade) receberam durante 30 dias consecutivos, por gavage (via oral), 40 mg/kg/dia de fenvalerato (grau técnico; 96,8% de pureza). O grupo controle recebeu apenas o veículo (óleo de milho), segundo o mesmo protocolo experimental. No final do tratamento, foram avaliados os seguintes parâmetros: peso corporal; peso absoluto de órgãos da reprodução, fígado e rins; níveis plasmáticos de testosterona; contagem de células germinativas no testículo e no epidídimo; morfologia espermática; estudo da fertilidade através de cruzamentos naturais e inseminação artificial in utero; contagem de espermatozóides ejaculados no útero; avaliação do comportamento sexual; análises do testículo e epidídimo em nível de microscopia óptica e eletrônica e avaliação da possível atividade estrogênica de diferentes doses do fenvalerato (0,4; 1,0; 4,0; 8,0 e 40 mg/kg) através do teste uterotrófico. A quantificação de resíduos de fenvalerato por Cromatografia Líquida de Alta Precisão (HPLC) em órgãos reprodutores e vitais e análises de proteínas espermáticas e epididimárias também foram realizadas. Os resultados foram comparados pelos testes ¿t¿ de Student e Mann-Whitney, dependendo da natureza da distribuição dos dados, enquanto os resultados do teste uterotrófico comparados pela ANOVA seguida pelo teste de Tukey. Os resultados da quantificação de fenvalerato revelaram que o piretróide foi retido em órgãos reprodutores (testículo e epidídimo) e vitais (cérebro e fígado). O tratamento com fenvalerato reduziu os pesos absolutos do testículo e do epidídimo. Além disso, o tratamento não provocou diminuição nos níveis plasmáticos de testosterona. Verificou-se também que os ratos tratados apresentaram redução na produção espermática no testículo e no número de espermatozóides no epidídimo. No entanto, não foi observado comprometimento na fertilidade desses machos quando acasalados com fêmeas controles. As análises morfológicas do testículo e epidídimo assim como as análises de proteínas espermáticas e epididimárias não mostraram alterações. Além disso, o fenvalerato, nas doses testadas, não apresentou atividade estrogênica in vivo. Concluiu-se que o fenvalerato, nestas condições experimentais, foi retido em órgãos reprodutores e vitais. O fenvalerato foi espermatotóxico, visto que reduziu tanto a produção quanto as reservas espermáticas dos animais tratados. No entanto, apesar dessa alteração, a fertilidade dos animais tratados não foi comprometida, uma vez que o rato tem uma grande eficiência reprodutiva, diferentemente do que acontece com o ser humano
Abstract: Fenvalerate is a synthetic pyrethroid insecticide widely used in agriculture to control a variety of insects. Although it is considered to be of low acute toxicity to mammals, studies have showed that pyrethroids can have estrogenic activity and can act as endocrine disruptors, causing important reproductive impairment in males. It is documented in the literature that the exposure of pregnant rats to fenvalerate decreased plasma testosterone levels and weights of seminal vesicle and vas deferens in male pups during adult life, besides alterations in their sexual behavior. It was also observed that adult rats exposed to formulated fenvalerate,by inhalation, exhibited a significant reduction in the testis weight and epididymal sperm count. Little is known about the mechanisms by which fenvalerate exerts its action on reproduction; thus, the objective of the present study was to investigate the estrogenic activity and the effects of fenvalerate on the reproductive system and fertility of adult male rats. For this, adult male rats (aged 90 days) received, for 30 consecutive days, by oral gavage, 40 mg/kg/day of fenvalerate (technical grade; 96.8% purity). The control group received only the vehicle (corn oil), in the same experimental conditions. At the end of the treatment, the following parameters were analyzed: body weight; absolute weight of reproductive organs, liver and kidneys; plasma testosterone levels; germ cell count in the testis and epididymis; sperm morphology; fertility tests by natural matings and artificial insemination in utero; ejaculated sperm counts in uterus; sexual behavior; analysis of testis and epididymis at the optical and electron microscopic levels, and evaluation of possible estrogenic activity of different doses (0.4; 1.0; 4.0; 8.0 and 40 mg/kg) of fenvalerate by the uterotrophic test. Fenvalerate residues were quantified using High Performance Liquid Chromatography (HPLC) in reproductive and vital organs; sperm and epididymal protein were also realized. The results were compared by Student-t and Mann-Whitney tests, according to the characteristics of each variable, while the results of the uterotrophic test were compared by ANOVA followed by the Tukey test. The results of fenvalerate quantification revealed that the pyrethroid was retained in reproductive (testis and epididymis) and vital organs (brain and liver). The treatment with fenvalerate decreased the absolute weights of testis and epididymis. Furthermore, the treatment did not provoke reduction of plasma testosterone levels. It was also verified that the treated rats presented a reduction in daily sperm production and in epididymal sperm number. The fertility tests did not reveal differences related to the treatment. The results of the fenvalerate quantification revealed high concentrations of insecticide residues in the epididymis, testis, brain and liver. The histopathology of the testis and epididymis as well as analysis of sperm and epididymal proteins did not show alterations. Moreover, fenvalerate, at the tested doses, did not present estrogenic activity in vivo. It was concluded that fenvalerate, in these experimental conditions, was retained in reproductive organs and was spermatotoxic, since it reduced sperm production and storage, but this alteration was not sufficient to compromise fertility by virtue of the high reproductive efficiency of rodents in contrast with humans
Doutorado
Biologia Celular
Doutor em Biologia Celular e Estrutural
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Sokolic, Ljiljana. "Olfactory discrimination in the rat." University of Sydney, 2009. http://hdl.handle.net/2123/4986.
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Doctor of Philosophy (PhD)Abstract Olfactory tasks are used very often with laboratory animals in studies of the neurobiology of learning and memory. Rats and mice are extremely sensitive in their detection and discrimination of odours, learn olfactory tasks rapidly, and can display higher order cognitive functions in olfactory tasks. This cognitive capacity may rival the ability of primates to learn analogous tasks with visual cues and most likely reflects strong anatomical connections between the olfactory bulbs and higher brain regions such as the piriform cortex, orbitofrontal cortex and hippocampus. The current thesis explored olfactory discrimination learning and performance in rats and had two principal aims. The first part of the thesis was oriented around odour masking phenomena in rats: the ability of one odour in a mixture to suppress detection of a second odour in that mixture. A specialized behavioural paradigm was developed to allow the study of odour masking in the rat. The second part of the thesis was pharmacological and determined whether the acquisition, reversal and performance of olfactory discriminations, and analogous auditory discriminations, are affected by two commonly used classes of drugs (benzodiazepines and cannabinoids). Together, these studies attempt to gain a better understanding of the nature of olfactory discrimination learning in rats, by using both psychophysical and pharmacological approaches, and to develop behavioural paradigms which may be used in future psychophysical and pharmacological studies. Following an introduction and review of olfactory and auditory studies in rat (Chapter 1), odour masking phenomena were studied in Chapter 2. The aliphatic aldehydes butanal (C4) and heptanal (C7) were used in the study. Aldehydes were of interest as this class of odorants abound in nature and may be important for rodents’ species-specific communication. Thirsty rats were initially trained to discriminate C4 and C7 in the olfactometer, using a go/no-go olfactory discrimination task. This involved rats learning to nose poke in an odour port and to lick a tube for a water reward on presentation of the rewarded component S+, while withholding licking at the tube when the other, unrewarded, aldehyde (S-) was presented. Odour mixtures (C4C7 or C7C4) were then introduced into the task as an additional non-rewarded condition (mixture S-). The concentration of the non-rewarded aldehyde in the mixture was then systematically decreased, while the concentration of the rewarded aldehyde was kept constant. When the non-rewarded aldehyde reached a critical low level in the mixture, rats started to make responses to the non-rewarded mixture (false alarms) showing that the S+ odour was suppressing the S- odour in the mixture, so the mixture was being responded to in the same manner as the S+ odour presented alone. Results also showed asymmetric suppression in the mixture condition, such that butanal suppressed detection of heptanal at a much lower concentration than vice versa. A second experiment demonstrated that when both butanal and heptanal were present in a binary mixture at the same concentration (10-6 volume %), rats responded to the mixture as if only butanal was present. Our findings are in agreement with human studies showing component interactions in binary mixtures of aldehydes. The molecular feature of carbon chain length appears to be a critical factor in determining the outcome of interactions between aldehydes at peripheral olfactory receptors, with smaller chain aldehydes better able to compete for receptor occupancy. Subsequent chapters explored the effects of two classes of commonly used drugs - benzodiazepines and cannabinoids - on olfactory and auditory discrimination in rats. Animal models such as the radial arm maze, Morris water maze and object recognition test are routinely used to test adverse and facilitatory effects of drugs on cognition in rodents. However, comparatively few pharmacological studies employ olfactory or auditory go/no-go paradigms. Thus, an important part of the present thesis was to assess the viability of using such paradigms in detecting pharmacological effects, and to identify whether such effects may be modality specific (i.e. whether a drug has a greater effect on olfactory or auditory tasks). In Chapter 3, the effects of benzodiazepines on olfactory discrimination tasks were explored. Rats were injected with the benzodiazepine drugs midazolam or diazepam and tested on discrimination tasks involving either the auditory and olfactory modality. Results showed that midazolam (0.5–2 mg/kg sc) did not affect the performance of a well-learned two-odour olfactory discrimination task, and moderately facilitated the performance of a go/no-go auditory discrimination task. On the contrary, midazolam (1 mg/kg) impaired the acquisition of a novel go/no-go olfactory discrimination task, as well as the reversal of a previously well-learned olfactory discrimination. However, midazolam did not affect the acquisition or reversal of an equivalent auditory discrimination task. The olfactory bulb and the piriform cortex are intimately involved in associative learning and behavioural aspects of olfactory performance, and have high concentrations of benzodiazepine receptors. These may therefore be possible neural substrates for the disruptive effects of benzodiazepines on olfactory learning. Findings from Chapter 4 indicated that the prototypical cannabinoid agonist delta-9-tetrahydrocanabinol (Δ9 THC) (0.3, 1 and 3 mg/kg) impairs auditory discrimination performance, but had no effect on equivalent olfactory discriminations. This is in marked contrast to the effects of benzodiazepines. Residual effects were observed, such that auditory discrimination performance was still impaired on the day following Δ9 THC administration. Delta-9-tetrahydrocanabinol effects were prevented by co-administration of the cannabinoid antagonist rimonabant (3 mg/kg). In addition, the anandamide hydrolysis inhibitor URB597 (0.1 and 0.3 mg/kg), which boosts levels of endogenous cannabinoids in the synapse, also impaired auditory discrimination performance, and this effect was also reversed by rimonabant. This study also assessed the effects of Δ9 THC (0.3, 1 and 3 mg/kg) and URB597 (0.1 and 0.3 mg/kg) on acquisition and reversal of novel olfactory discriminations. Results showed that Δ9 THC impairs olfactory reversal learning without affecting acquisition of the original discrimination. It is argued that this reversal deficit may be part of a wider capacity for cannabinoids to impair cognitive flexibility. The final Chapter (General Discussion) discusses the relevance and implications of the combined findings. The results add significantly to our current understanding of perceptual, learning and memory processes involving the olfactory modality in rats. With respect to olfactory perception, this thesis introduced a new behavioural paradigm, which can be used to assess component suppression in mixtures, and may be of use in future psychophysical studies involving rodents or other species. With respect to learning and memory, the thesis provides novel information on the disruptive effects of benzodiazepines and cannabinoids on olfactory and auditory tasks. It is concluded that go/no-go olfactory and auditory discrimination tasks in rats can provide a useful platform for assessing the disruptive and modality-specific effects of drugs on learning, performance and cognitive flexibility. Future studies might expand the range of drugs tested on these paradigms and might consider chronic as well as acute drug effects.
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Irvine, Rodney James. "Nociception in the hypertensive rat." Title page, contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phi7185.pdf.
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Birzniece, Vita. "Neuroactive steroids and rat CNS." Doctoral thesis, Umeå : Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-296.
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Oliet, Stéphane H. R. "Osmoreception in rat supraoptic neurons." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28874.
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The osmotic control of neurohypophysial hormone release is mediated by central and peripheral osmoreceptors which perceive changes in fluid osmolality. The mechanism underlying signal transduction in these structures, however, has remained obscure. Supraoptic neurons, which synthesize and secrete the neurohypophysial hormones, are themselves recognized to be osmoreceptors. Combined electrophysiological and micromorphometric measurements were therefore obtained in acutely isolated rat supraoptic neurons to determine the cellular basis for signal transduction in osmoreception. Osmotically-evoked changes in cell volume and a gadolinium-sensitive cationic conductance were found to be temporally and proportionally related. In agreement, cell-attached patch-clamp recordings revealed the presence of gadolinium-sensitive cationic channels modulated in response to osmotic stimuli. The mean closed time of these channels was found to increase as a function of changes in membrane tension mediated either by external osmotic perturbation, or by application of pressure inside the patch pipette. The ionic selectivity, density, mechanosensitivity, and pharmacological properties of these channels are consistent with an involvement in the mechanism underlying osmosreception in supraoptic neurons.
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Parker, Ruth E. "The rat interleukin-4 receptor." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318893.
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Walter, D. J. "Fibre metabolism in the rat." Thesis, University of Edinburgh, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370595.
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Benjamin, Irving Stuart. "Portacaval transposition in the rat." Thesis, University of Glasgow, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293482.
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Odom, N. J. "Lung preservation in the rat." Thesis, University of Newcastle Upon Tyne, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234476.
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Benns, L. M. "Meningeal innervation in the rat." Thesis, University of Reading, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376821.
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Сулим, Григорій Анатолійович, Григорий Анатольевич Сулим, Hryhorii Anatoliiovych Sulym, Микола Сергійович Линдін, Николай Сергеевич Лындин, Mykola Serhiiovych Lyndin, Владислав Володимирович Сікора, et al. "Ultraviolet impact on rat skin." Thesis, Springer, 2020. https://essuir.sumdu.edu.ua/handle/123456789/81258.
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The aim of our study was to establish a >model imitating of UV-B (wavelength peak is 311 nm) therapy for rat’s skin and to find match macroscopical and following histological skin changes including melanocytes spreading and melanin distribution.
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Kwok, Hon Hung. "Immunolesioning in the rat brain." HKBU Institutional Repository, 1999. http://repository.hkbu.edu.hk/etd_ra/234.
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Sokolic, Ljiljana. "Olfactory discrimination in the rat." Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/4986.
Full textAbstract:
Abstract Olfactory tasks are used very often with laboratory animals in studies of the neurobiology of learning and memory. Rats and mice are extremely sensitive in their detection and discrimination of odours, learn olfactory tasks rapidly, and can display higher order cognitive functions in olfactory tasks. This cognitive capacity may rival the ability of primates to learn analogous tasks with visual cues and most likely reflects strong anatomical connections between the olfactory bulbs and higher brain regions such as the piriform cortex, orbitofrontal cortex and hippocampus. The current thesis explored olfactory discrimination learning and performance in rats and had two principal aims. The first part of the thesis was oriented around odour masking phenomena in rats: the ability of one odour in a mixture to suppress detection of a second odour in that mixture. A specialized behavioural paradigm was developed to allow the study of odour masking in the rat. The second part of the thesis was pharmacological and determined whether the acquisition, reversal and performance of olfactory discriminations, and analogous auditory discriminations, are affected by two commonly used classes of drugs (benzodiazepines and cannabinoids). Together, these studies attempt to gain a better understanding of the nature of olfactory discrimination learning in rats, by using both psychophysical and pharmacological approaches, and to develop behavioural paradigms which may be used in future psychophysical and pharmacological studies. Following an introduction and review of olfactory and auditory studies in rat (Chapter 1), odour masking phenomena were studied in Chapter 2. The aliphatic aldehydes butanal (C4) and heptanal (C7) were used in the study. Aldehydes were of interest as this class of odorants abound in nature and may be important for rodents’ species-specific communication. Thirsty rats were initially trained to discriminate C4 and C7 in the olfactometer, using a go/no-go olfactory discrimination task. This involved rats learning to nose poke in an odour port and to lick a tube for a water reward on presentation of the rewarded component S+, while withholding licking at the tube when the other, unrewarded, aldehyde (S-) was presented. Odour mixtures (C4C7 or C7C4) were then introduced into the task as an additional non-rewarded condition (mixture S-). The concentration of the non-rewarded aldehyde in the mixture was then systematically decreased, while the concentration of the rewarded aldehyde was kept constant. When the non-rewarded aldehyde reached a critical low level in the mixture, rats started to make responses to the non-rewarded mixture (false alarms) showing that the S+ odour was suppressing the S- odour in the mixture, so the mixture was being responded to in the same manner as the S+ odour presented alone. Results also showed asymmetric suppression in the mixture condition, such that butanal suppressed detection of heptanal at a much lower concentration than vice versa. A second experiment demonstrated that when both butanal and heptanal were present in a binary mixture at the same concentration (10-6 volume %), rats responded to the mixture as if only butanal was present. Our findings are in agreement with human studies showing component interactions in binary mixtures of aldehydes. The molecular feature of carbon chain length appears to be a critical factor in determining the outcome of interactions between aldehydes at peripheral olfactory receptors, with smaller chain aldehydes better able to compete for receptor occupancy. Subsequent chapters explored the effects of two classes of commonly used drugs - benzodiazepines and cannabinoids - on olfactory and auditory discrimination in rats. Animal models such as the radial arm maze, Morris water maze and object recognition test are routinely used to test adverse and facilitatory effects of drugs on cognition in rodents. However, comparatively few pharmacological studies employ olfactory or auditory go/no-go paradigms. Thus, an important part of the present thesis was to assess the viability of using such paradigms in detecting pharmacological effects, and to identify whether such effects may be modality specific (i.e. whether a drug has a greater effect on olfactory or auditory tasks). In Chapter 3, the effects of benzodiazepines on olfactory discrimination tasks were explored. Rats were injected with the benzodiazepine drugs midazolam or diazepam and tested on discrimination tasks involving either the auditory and olfactory modality. Results showed that midazolam (0.5–2 mg/kg sc) did not affect the performance of a well-learned two-odour olfactory discrimination task, and moderately facilitated the performance of a go/no-go auditory discrimination task. On the contrary, midazolam (1 mg/kg) impaired the acquisition of a novel go/no-go olfactory discrimination task, as well as the reversal of a previously well-learned olfactory discrimination. However, midazolam did not affect the acquisition or reversal of an equivalent auditory discrimination task. The olfactory bulb and the piriform cortex are intimately involved in associative learning and behavioural aspects of olfactory performance, and have high concentrations of benzodiazepine receptors. These may therefore be possible neural substrates for the disruptive effects of benzodiazepines on olfactory learning. Findings from Chapter 4 indicated that the prototypical cannabinoid agonist delta-9-tetrahydrocanabinol (Δ9 THC) (0.3, 1 and 3 mg/kg) impairs auditory discrimination performance, but had no effect on equivalent olfactory discriminations. This is in marked contrast to the effects of benzodiazepines. Residual effects were observed, such that auditory discrimination performance was still impaired on the day following Δ9 THC administration. Delta-9-tetrahydrocanabinol effects were prevented by co-administration of the cannabinoid antagonist rimonabant (3 mg/kg). In addition, the anandamide hydrolysis inhibitor URB597 (0.1 and 0.3 mg/kg), which boosts levels of endogenous cannabinoids in the synapse, also impaired auditory discrimination performance, and this effect was also reversed by rimonabant. This study also assessed the effects of Δ9 THC (0.3, 1 and 3 mg/kg) and URB597 (0.1 and 0.3 mg/kg) on acquisition and reversal of novel olfactory discriminations. Results showed that Δ9 THC impairs olfactory reversal learning without affecting acquisition of the original discrimination. It is argued that this reversal deficit may be part of a wider capacity for cannabinoids to impair cognitive flexibility. The final Chapter (General Discussion) discusses the relevance and implications of the combined findings. The results add significantly to our current understanding of perceptual, learning and memory processes involving the olfactory modality in rats. With respect to olfactory perception, this thesis introduced a new behavioural paradigm, which can be used to assess component suppression in mixtures, and may be of use in future psychophysical studies involving rodents or other species. With respect to learning and memory, the thesis provides novel information on the disruptive effects of benzodiazepines and cannabinoids on olfactory and auditory tasks. It is concluded that go/no-go olfactory and auditory discrimination tasks in rats can provide a useful platform for assessing the disruptive and modality-specific effects of drugs on learning, performance and cognitive flexibility. Future studies might expand the range of drugs tested on these paradigms and might consider chronic as well as acute drug effects.
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Lewis, Beverley Anne. "Cell biology of rat spermatozoa." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/23087.
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The purpose of the research presented in this thesis was to investigate the cell biology of rat spermatozoa. An additional aim was to utilise the knowledge obtained to aid the development of in vitro functional tests for the assessment of rat sperm fertility and identify potential markers of normal epididymal maturation. As mammalian spermatozoa migrate through the epididymis, they acquire the potential for fertilisation, characterised by the acquisition of the ability to express co-ordinated movement and the competence to undergo capacitance. The mechanisms by which epididymal maturation confers upon mammalian spermatozoa the potential to capacitate is poorly understood. These studies investigated the impact of epididymal maturation on the signal transduction pathways regulating tyrosine phosphorylation using the laboratory rat as an animal model, since this signal transduction pathway is thought to be central to the attainment of a capacitated state and expression of hyperactivated motility, both of which are prerequisites for fertilisation. Western Blot and immunocytochemical analysis demonstrated that epididymal maturation is associated with a progressive loss in phosphotyrosine expression located to the acrosomal domain. These differences in phosphotyrosine expression between caput and caudal epididymal spermatozoa appeared to reflect the normal in vivo situation. In addition, epididymal maturation of rat spermatozoa is also associated with an acquired competence to respond to high levels of intracellular cAMP by phoshorylating tyrosine residues on the sperm tail. Epididymal maturation also led to unique differences in the generation of reactive oxygen species (ROS) by spermatozoa obtained from the caput and caudal regions of the epididymis. Spermatozoa from both regions of the epididymis spontaneously generated equal levels of O2 whereas only mature caudal spermatozoa generated significant levels of H2O2. In contrast, although both caput and caudal spermatozoa generated increased O2-. in response to NADPH, induced levels were significantly greater in the immature caput cells.
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Wallace, Timothy J. "Characterization of rat pulmonary carboxylesterase." VCU Scholars Compass, 1999. https://scholarscompass.vcu.edu/etd/5616.
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The 1839 bp cDNA for rat pulmonary carboxylesterase was cloned by reverse transcription polymerase chain reaction (RT PCR) from total rat lung RNA using specific primers derived from the 5' and 3' untranslated regions of rat hepatic cholesteryl ester hydrolase (CEH). The unique cDNA was sequenced and found to have 99% homology with hepatic CEH. This homology extends to the predicted amino acid sequences which show only six amino acid residue differences in the coding region: three conserved and three nonconserved changes. However, the catalytic activitites of the two proteins are dramatically different. While CEH hydrolyzes cholesterol oleate, the pulmonary carboxylesterase has no activity towards this substrate. The active recombinant lung carboxylesterase was purified using a baculovirus expression system. The substrate specifities were determined using p-nitrophenyl acetate, p-nitrophenyl caprylate and cholesterol oleate. Also, the KM, Vmax and pH optima were determined for each substrate. Comparison of the substrate specificities of the recombinant pulmonary carboxylesterase with the recombinant CEH further establish the critical role of the six amino acid residues in determining the differences in the catalytic activities of these two proteins. Cumulative mutations were made in the lung carboxylesterase sequence to those of the hepatic CEH sequence, in order to determine the role(s) of these six amino acid residues in conferring cholesterol oleate hydrolytic activity. These studies showed that GIn186 is vital for activity towards hydrophilic substrates, while the region around amino acid residue 500 consisting of Ser491, Lys492, Asn506 and Asn504 may be responsible for the absence of catalytic activity towards hydrophobic substrates.
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Ho, Peter D. "Regulation of morphology and intracellular calcium by Ras in rat neonatal cardiac myocytes /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2000. http://wwwlib.umi.com/cr/ucsd/fullcit?p9984293.
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Lee, Gabriel Y. F. "Origin of macrophages in rat syringomyelia : an investigative study using rat radiation bone marrow chimeras /." Title page, table of contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09MS/09msl478.pdf.
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Pahre, Hauke. "Das Recht des Europäischen Rates : eine Untersuchung im Lichte aktueller Entwicklungen der Europäischen Union /." Frankfurt, M. ; Berlin Bern Bruxelles New York, NY Oxford Wien : Lang, 2008. http://d-nb.info/989695905/04.
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Rolfe, David F. S. "The contribution of mitochondrial proton leak to the standard metabolic rate of a rat." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339591.
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Nicolescu-Catargi, Bogdan. "Resténose après angioplastie dans trois modèles de rats diabétiques et chez le rat normoglycémique." Bordeaux 2, 2001. http://www.theses.fr/2001BOR28918.
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L'incidence élevée de la resténose après angioplastie du patient diabétique incite à explorer les mécanismes physiopathologiques qui peuvent en être la cause. Cependant l'étude de la particularité de la réponse de la paroi artérielle à l'angioplastie dans le contexte du diabète sucré se heurte au manque de modèle expérimental idéal pour l'étude de l'angioplastie d'une part et du manque de modèle animal mimant le diabète de type 2 d'autre part. Nous avons montré dans un premier temps que la resténose occlusive et non occlusive de l'artère carotide après angioplastie est significativement plus importante dans un modèle de rat présentant un diabète polygénique proche du type 2 (le rat GK), par rapport au rat normoglycémique. La resténose n'est pas reproduite dans le modèle de diabète induit par la streptozotocine, avec ou sans insuline. L'hyperplasie intimale est la principale cause de la resténose non occlusive chez le rat GK. Les expressions de la fibronectine, et de TGF-β constituants majeurs de la matrice extracellulaire, sont augmentées dans ce modèle. L'origine adventicielle des cellules qui constituent l'hyperplasie intimale a été confirmée dans un deuxième temps chez le rat normal. En réponse au traumatisme artériel, les cellules de l'adventice ont la capacité de se différencier en myofibroblastes, de proliférer et migrer vers la lumière artérielle. Dans un troisième temps, l'étude comparative de la réaction adventicielle a montré que la prolifération cellulaire est plus importante chez le rat GK et qu'elle est suppléée par une angiogenèse adventicielle. L'hyperplasie intimale est corrélée à la néoangiogenèse adventicielle. Les expressions des facteurs HIF-1α et de VEGF dans la paroi artérielle suggèrent que l'hypoxie adventicielle au moment de la compression de l'artère, possiblement majorée par la microangiopathie des vasa vasorum, en soit la cause. Ce résultat expérimental peut expliquer la fréquence accrue de la resténose chez le patient diabétique porteur de microangiopathie. D'autre part, bien que la causalité entre angiogenèse et hyperplasie ne soit pas établie par cette étude mais à la lumière de publications récentes, notre observation incite à la prudence pour l'utilisation du facteur proangiogénique VEGF dans le contexte du diabète sucré et de l'angioplastieAtheosclerotic stenosis and its ischemic complications lead to the need for arterial reconstruction. However, restenosis after baloon angioplasty that results from both intimal hyperplasia and arterial remodeling lead to restenosis, especially in the setting of diabetes mellitus. Therefore the study of restenosis in diabetes (a major cardiovascular risk factor) is of importance. However the ideal animal model to study restenosis on one hand and the animal model that mimics type 2 diabetes in humans on the other hand are still lacking. Furthermore, many of the potential mechanisms promoting restenosis in diabetic patients are related to elevated glucose or insulin levels, or both, but most of them are hypothetical. We have studied the rat carotid artery subjected to balloon injury in three models of diabetic rats (streptozotocin, streptozotocin treated with insulin and Goto-Kakizaki (GK), a genetic model of type 2 diabetes) in comparison of normal, normoglycemic rats. Arterial restenosis after balloon angioplasty was the highest in the GK rats. Intimal hyperplasia played the main role in the lumen loss after angioplasty together with the enhanced expression of TGF and fibronectin, whereas arterial remodeling was the main mechanism in the other models and in the normal rat. We further confirmed the implication of the adventitial layer in neointimal formation. Finally, we have shown that cell proliferation in the adventitial layer was the highest in the GK rat and that adventitial proliferation is supplied by an adventitial angiogenesis. We further found a close correlation between the intimal hyperplasia area and angiogenesis indexes in the adventitia layer. Accordingly, we have found enhanced expressions of HIF-1α (Hypoxia Inducible Factor) and VEGF (Vascular Endothelial growth Factor) suggesting a majpr role of hypoxia in arterial healing and restenosis after restenosis in the GK rat. In conclusion we have shown that intimal hyperplasia is the main mechanism of restenosis in a genetic model of type 2 diabetes, in accordance with most of clinical studies. We suggest a direct implication of the adventitial layer supplied by angiogenesis in restenosis. Even if causality is not established by our study, we suggest the use of recombinant VEGF with caution for revascularisation in the setting of diabetes, since the intimal hyperplasia may be enhanced
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Dethy, Sophie. "Investigation "in vivo" du système dopaminergique présynaptique chez le rat sain et le rat rendu hémiparkinsonien." Doctoral thesis, Universite Libre de Bruxelles, 1998. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211976.
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Mokhtar, Najat. "Etude de la réponse métabolique du coeur in vivo à un traitement chronique à l'isoprénaline et à l'hypoxie aiguë chez le rat et chez le cobaye." Dijon, 1985. http://www.theses.fr/1985DIJOS050.
Full textAbstract:
La réponse métabolique de l'organisme entier et du coeur in vivo à la privation aiguë d'O2 et à un traitement chronique à l'Isoprénaline (Iso, 5mg. Kg-1. J-1 ; 7 j. ), a été étudiée chez des rats Sprague Dawley (R) et des Cobayes Dunkin Hartley (C), mâles, âgés de 10 à 12 semaines. Une partie du travail a consisté à appliquer la technique isotachophorétique à la détermination des métabolites énergétiques myocardiques. L'objectif du travail a consité à déterminer simultanément des concentrations de métabolites circulants et myocardiques en tenant compte des réserves glycogéniques de l'organisme [. . . ].
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Oiso, Yutaka, Hiroshi Nagasaki, and Hisashi Yokoi. "Transgenic rat models of vasopressin overexpression." Nagoya University School of Medicine, 2003. http://hdl.handle.net/2237/5393.
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Ejdesjö, Andreas. "Teratogenic Predisposition in Diabetic Rat Pregnancy." Doctoral thesis, Uppsala universitet, Institutionen för medicinsk cellbiologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-178175.
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Pre-gestational diabetes increases the risk of congenital malformation in the offspring and both morbidity and mortality in the diabetic mother and her offspring. During pregnancy, high glucose levels act as a teratogen through several cellular and biochemical pathways and increased production of reactive oxygen species (ROS) has a central role in diabetic embryopathy. The aim of this work was to investigate the importance of genetic predisposition for congenital malformations and to study the genes involved in the teratogenic process of diabetic pregnancy. The crossbreeding of two rat strains, with both low and high incidence of diabetes-induced malformations, indicated that strain-specific maternal factors, such as disturbed serum levels of amino acids, triglycerides, and β-hydroxybutyrate, were associated with malformation. In addition, disturbed fetal expression of genes involved in ROS defense and development (Shh, Bmp4, Ret and Gdnf) in mandible and heart, and decreased activity of Gapdh and Aldose Reductase were associated with the teratogenic process, and the trans-generational heredity of the mother determined the type of malformations induced by maternal diabetes. In rat embryos, a diabetic environment in utero changed the expression of genes involved in ROS defense (Nrf2, Gpx1 and Cat), development of mandible and heart (Msx2, Shh, Bmp4, Ret and Gdnf), and neural tube closure and apoptosis (Pax3 and p53). The changes were divergent with tissue-specific alterations of gene expression in developing mandible, heart anlage, and whole embryo. Disruption of the Receptor for Advanced Glycation End products (RAGE) had a protective effect against diabetic embryopathy in mice, and the blockage of RAGE diminished ROS production in the offspring: this supported oxidative stress being a necessary etiological component in diabetic embryopathy. Maternal metabolic state and genetic susceptibility influence fetal outcome in experimental diabetic pregnancy. Disturbed protection against oxidative stress and tissue-specific derangements in the expression of developmental genes play pivotal roles in the teratogenic mechanism, and enhanced levels of Advanced Glycation End products (AGE) and RAGE-induced oxidative stress are involved in diabetic dysmorphogenesis.
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Tumelty, James Martin. "Calcium imaging in rat retinal arterioles." Thesis, Queen's University Belfast, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486231.
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With the use ofconfocal microscope, the work presented in this thesis has for the first time identified spontaneous Ca2+sparks and Ca2+oscillations in intact retinal arteriole smooth muscle cells. Ca2+sparks may act as building blocks that can summate to interventions that modified ci+ sparks also modified Ca2+oscillations. The mechanisms include, release of Ca2+from ryanodine sensitive stores, the sarcoplasmic reticulum Ca2+-ATPase and Ca2+influx from the extracellular space. However, the influx of Ca2+is not tightly correlated to spontaneous Ca2+release. The effects of the vasoconstrictor, endothelin-l on subcellular Ca2+signals was examined and was found to evoke Ca2+ oscillations. Further studies showed that endothelin-l' increases the frequency ofCa2+ oscillations by binding to the endothelin-A receptor with the subsequent release ofCa2+ from IP3 sensitive and ryanodine sensitive stores. A further increase in the frequency of Ca2+oscillations is seen with the inhibition ofvoltage gated K+ channels, suggesting these channels act to suppress membrane excitability.
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Hultin, Magnus. "Turnover of chylomicrons in the rat." Doctoral thesis, Umeå universitet, Institutionen för medicinsk kemi och biofysik, 1995. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-102338.
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Mechanisms involved in the clearance of chylomicrons and aspects of the interactions at the vascular endothelium were studied in the rat. The poly-anion heparin, known to release lipoprotein lipase (LPL) from the vascular endothelium, enhanced the clearance of chylomicrons. Five minutes after heparin injection, the clearance of chylomicron triglycerides and retinyl esters was markedly accelerated. The rapid initial clearance was followed by a slower clearance of heavily lipolyzed chylomicrons. In contrast, one hour after heparin the clearance of both triglycerides and retinyl esters was retarded. This decreased removal of chylomicrons coincided with a decrease in the heparin releasable LPL activity, indicating that the previous release to plasma by heparin had resulted in net loss of functional LPL in the tissues. The poly-cation protamine released hepatic lipase and some LPL from their binding sites to plasma. One hour after protamine, plasma triglyceride levels were increased, indicating that chylomicron removal was impeded. It has been speculated that protamine inactivates LPL in vivo, but this was not the case. Ten minutes after injection of protamine normal amounts of LPL could be released by heparin. Thus, the accumulation of plasma triglycerides was not due to a rapid inactivation of LPL by protamine. LPL has specificity for sn-1,3-ester bonds. To investigate if this specificity is important in vivo, a lipid emulsion containing medium-chain fatty acids (MCFA) in the sn-1,3-position and long-chain fatty acids (LCFA) in the sn-2-position was synthesized, as well as an emulsion containing MCFA-TG mixed with LCFA-TGs (MMM/LLL). In vitro experiments showed large differences in the hydrolysis of the emulsions, but in vivo there were only small differences in the metabolism. To further study if lipid emulsions are cleared by the same mechanisms as chylomicrons, an emulsion was made by the same formulation as Intralipid® with addition of 3H-triolein and ,4C-cholesteryl ester. As measured by the removal of cholesteryl esters, the emulsion was cleared at the same rate as was chylomicrons. The triglyceride label was, however, removed more slowly from the emulsion droplets than from chylomicrons. Together with the lower recirculation of labeled free fatty acids (FFA) in plasma, this suggests that there was less lipolysis of the emulsion. The current view that removal of lipid emulsions in vivo is mainly dependent on LPL-mediated hydrolysis might thus not be correct. To further analyze the metabolism of chylomicrons, a compartmental model was developed. In this process, the distribution volume for chylomicrons was shown to be larger than the blood volume, a model for the metabolism of FFA in the rat was validated, and the full tissue distribution of injected chylomicrons was determined. According to the model, about half of the triglyceride label was removed from the circulation together with the core label while for the emulsion this number was about 80 %. In fasted rats all labeled fatty acids appeared to mix with the plasma FFA pool, while in fed rats about one-fifth of the fatty acids did not mix with the FFA but was apparently channeled directly to tissue metabolism.Diss. (sammanfattning) Umeå : Umeå universitet, 1995, härtill 5 uppsatser.
digitalisering@umu.se
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Dadgar, Anoushiravan. "Studies on rat gastrointestinal neuropeptide Y." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/27410.
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A sensitive and specific radioimmunoassay (RIA) for Neuropeptide Y (NPY) was developed and quantitation, characterization and release studies were performed.
The development of the RIA required the purification of the NPY tracer due to both multiple iodinated products resulting from the five tyrosine residues in its amino acid sequence, and the presence of unlabelled NPY. Ion-exchange and reverse phase high performance chromatography (HPLC) purification of ¹²⁵I-NPY were performed. Optimal purification of ¹²⁵I-NPY was achieved using a HPLC with a μBondapak C₈ column and a 45-50% acetonitrile concentration gradient. A polyethylene glycol separation technique was used in conjunction with the HPLC purified tracer to improve assay conditions.
Although many studies aimed at elucidating the actions of NPY have been performed, little information is available on the distribution of gastrointestinal (GI) NPY in the rat. Therefore the NPY-immunoreactivity (IR) in extracts of the various regions of the GI tract were determined using the developed RIA. The tissue content of NPY was found to be highest in the various segments of the rat stomach, with a decreasing trend in NPY-IR down the GI tract until the level of the ascending colon where an increase was detected. Characterization studies on the tissue extracts were performed using gel filtration chromatography and HPLC. One immunoreactive species was detected in the corpus and ileum extracts using gel filtration chromatography, and in the corpus and colon extracts using HPLC. This immunoreactive species eluted in a position similar to synthetic porcine NPY and later than peptide YY (PYY).
In the physiological investigation of the the role of neuropeptides in the regulation of GI functions, release studies are crucial. The presence of high levels of NPY-IR in the stomach allowed the investigation of the release mechanisms of NPY in the perfused isolated rat stomach. However, due to the low basal secreted levels of NPY in comparison with other gastric peptides, as well as the enzymatic degradation and/or peptide uptake that occurs in the stomach vasculature, certain steps had to be taken to allow for the detection of the endogenously released peptide. Sep Pak extraction was found to be required to concentrate the endogenously released peptide. Proteolytic inhibitors were also added to the perfusate to reduce enzymatic degradation. A low basal level of NPY was detected which ranged from 98 to 147 fmole/min. Neuropeptide Y was found to be released into the gastric vasculature in response to high potassium depolarization.
A few studies have been performed on cholinergic effects on NPY release, however no direct release studies have been performed on NPY-containing neurones innervating the stomach. Therefore, the actions of cholinergic agonists and antagonists on NPY secretion in the isolated perfused rat stomach were investigated. Acetylcholine and the nicotinic ganglionic agonist dimethyl-phenyl-piperazinium (DMPP) stimulated NPY secretion. The acetylcholine-stimulated secretion was not blocked by the cholinergic muscarinic antagonist atropine and was partially blocked by the ganglionic cholinergic antagonist hexamethonium.
The effects of α- and β-adrenergic agonists and antagonists on NPY secretion into the stomach vasculature were investigated in order to elucidate possible adrenergic release mechanisms. There were conflicting results on the α-adrenergic release of NPY. Both the α-adrenergic antagonist phentolamine and the agonist phenylephrine had a stimulatory effect on NPY secretion in the stomach. The β -adrenergic agonist isoproterenol had a stimulatory effect on NPY release. The β -adrenergic antagonist propranolol caused an initial small increase in mean NPY levels followed by a decrease, but this was not found to be statistically significant.
These studies demonstrated the presence of NPY in the GI tract of the rat with the highest content being in the rat stomach. There are cholinergic stimulatory mechanisms involved in the secretion of NPY which are partially ganglionically mediated. The results did not conclusively demonstrate as to whether there is an α-adrenergic stimulatory or
inhibitory action on NPY-containing neurones in the gut, however preliminary release studies suggest there is a β-adrenergic stimulatory mechanism involved in NPY secretion.Medicine, Faculty of
Cellular and Physiological Sciences, Department of
Graduate
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Rooney, Thomas A. "Inositol phospholipid metabolism in rat brain." Thesis, University of Leicester, 1987. http://hdl.handle.net/2381/33609.
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In the studies described in this thesis the ability of muscarinic and ?1-adrenoceptor, as well as depolarising stimuli to initiate phosphoinositide metabolism in various regions of rat brain were examined. Furthermore, the ability of these stimuli to initiate phosphoinositide hydrolysis in developing brain was observed. Both muscarinic and ?1-adrenoceptor-induced phosphoinositide hydrolysis have marked regional distributions in rat brain. This regional distribution of functional responsiveness seems to correlate reasonably well with measurements of known receptor density. It is also clear that there is no variability in the coupling of both of these receptors in rat brain, thus implying a relationship between the functional responses and receptor occupancy. Pirenzepine appears to be able to differentiate between muscarinic receptor-induced phosphoinositide responses in the hindbrain from those in the forebrain regions. Both elevated K+ and veratrine can initiate phosphoinositide hydrolysis in rat brain. The regional responses to elevated K+ seem, at least, in part to be due to transmitter release, although a role for voltage-sensitive Ca++ channels in such responses is indicated by the effects produced by dihydropyridine Ca++ channel antagonists and activators. Muscarinic and ?1-adrenoceptors show different developmental patterns of phosphoinositide responsiveness. The ?1-adrenoceptor seems to be more efficiently coupled during the first two weeks of postnatal development whereas the muscarinic receptor shows no variability in coupling. Instead, carbachol produces supramaximal responses in young rats. Lithium also potentiates [3H]-InsP1 and [3H]-InsP2 accumulations more in young rats. Moreover lithium produces a time-dependent inhibition of [3H]-InsP3 and [3H]-InsP4 in both young and adult rats. Physostigmine produces no enhancement of the response to elevated K+ in young rats. Furthermore, brain slices from young rats seem to be more sensitive to the Ca++ channel activator BAY-K8644. The significance of these results are discussed in the text.
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Ashley, George Russell. "EphB signalling in rat prostate development." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/26151.
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In male mammals, the formation of the prostate gland is driven by androgens and involves cell-cell signalling between mesenchymal and epithelial cells. Gene profiling studies of prostate mesenchyme, using serial analysis of gene expression (SAGE), identified many transcripts that encode potential regulators of prostate development. The studies identified transcripts expressed in the ventral mesenchymal pad (VMP), a subset of the prostate mesenchyme known to express key growth factors and to regulate prostate organ development. These candidate mRNAs were used in a whole mount in-situ hybridisation (WISH) screen to identify those showing mesenchyme specific expression. The transcripts selected for WISH analysis were placed in three groups. The first group of transcripts were identified as enriched in the VMP based upon statistical analysis of their SAGE tag count. The second group of transcripts shared a SAGE tag count that was not statistically significant, and were a control for the first group. The third group encompassed transcripts that encoded either secretory or transmembrane proteins that were likely mediators of cell-cell communication. From 194 candidates, 30 were analysed by WISH and 13 were identified as mesenchymal. The tyrosine kinase receptor, EphB3, was selected from the WISH analysis and its role in prostate development was examined. EphB signalling has been characterised as a chemotactic guidance cue in neuronal development and has also been implicated in organogenesis of the kidney, lung and colon. The Eph tyrosine kinase family is the largest of its type and is divided into two classes of receptor, Eph A and EphB. The EphB family has five receptors (EphB 1-4, B6) and three ligands (EphrinBl-3) in mammals. The EphrinB ligands are transmembrane proteins. PCR analysis was used to examine the expression of the EphB and EphrinB transcripts in the developing rat prostate. The PCR analysis showed that mRNAs for the EphB2 and EphB3 receptors, and the EphrinB 1 and EphrinB2 ligands, were highly expressed in the rat prostate compared with the other EphB and EphrinB family members. The PCR analysis did not establish whether EphB receptors or EphrinB ligands were expressed in epithelia, mesenchyme or both. The EphB2 and EphB3 receptors, and the EphrinB 1 and EphrinB2 ligands, were further characterised by WISH, quantitative real-time PCR and immunohistochemical analysis during prostate development. At both the mRNA and protein levels, EphB3 and EphrinB 1 were expressed in a restricted area of the prostate mesenchyme, in close association with the developing epithelial buds. The EphB3 and EphrinB 1 transcripts were detected by the SAGE analysis, suggesting that they were expressed in the mesenchyme. The EphB2 and EphrinB2 transcripts were not detected by the SAGE analysis, suggesting that they were expressed in the epithelium. The EphB2 receptor and EphrinB2 ligand were predominantly expressed in the developing epithelial buds, as shown by immunohistochemical analysis. The SAGE analysis of VMP mesenchyme identified EphB3 and EphrinB 1 but not EphB2 and EphrinB2. This was consistent with their expression in mesenchyme or epithelium respectively. The addition of EphB2-Fc and EphB3-Fc to in vitro organ cultures of neonatal prostates, acting as a ligand trap, decreased prostate growth. The addition of EphrinB 1-Fc and EphrinB2-Fc ligands increased prostate organ size. The addition of EphrinB 1-Fc and EphrinB2-Fc produced a significant increase in the mesenchymal and epithelial cell proliferation rates. This increase in cell proliferation in response to EphrinB 1-Fc and EphrinB2-Fc was consistent with the observed increase in prostate organ size. The addition of EphB2-Fc and EphB3-Fc produced no significant increase in the mesenchymal and epithelial cell proliferation rates. This lack of a significant increase in cell proliferation in response to EphB2-Fc and EphB3-Fc was consistent with the observed decrease in prostate organ size. These findings suggest a role for EphB signalling in the regulation of prostate growth. The addition of either EphB-Fc or EphrinB-Fc proteins to in vitro organ cultures resulted in a decrease epithelial branching morphogenesis. Larger epithelial buds were observed in organs treated with EphrinB 1-Fc and EphrinB2-Fc, when compared to control organs. No visible change in the size of the epithelial buds was observed in response to EphB-Fc treatment. Furthermore, p63 and Smooth Muscle Actin immunohistochemical analysis of EphrinBl-Fc and EphrinB2-Fc treated organs showed larger epithelial buds, and proliferation analysis showed greater epithelial cell proliferation in EphrinB-Fc treated organs. The increased size of each epithelial bud may be caused by the decreased epithelial branching and the increased epithelial proliferation rate, in response to the addition of EphrinB-Fc proteins. These findings suggest a role for EphB-EphrinB signalling in the regulation of prostate epithelial branching. Collectively, we report the first reported functional link between EphB signalling and prostate development. EphB-EphrinB signalling may act as a novel juxtacrine or autocrine signal within the mesenchyme or as a novel paracrine signalling mechanism during prostate organogenesis.
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Hu, Ying. "Optic nerve regeneration in adult rat." University of Western Australia. School of Anatomy and Human Biology, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0080.
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[Truncated abstract] There is limited intrinsic potential for repair in the adult human central nervous system (CNS). Dysfunction resulting from CNS injury is persistent and requires prolonged medical treatment and rehabilitation. The retina and optic nerve are CNSderived, and adult retinal ganglion cells (RGCs) and their axons are often used as a model in which to study the mechanisms associated with injury, neuroprotection and regeneration. In this study I investigated the effects of a variety of strategies on promoting RGC survival and axonal regeneration after optic nerve injury, including the use of reconstructed chimeric peripheral nerve (PN) grafts, gene therapy, and intraocular application of pharmacological agents and other factors . . . C3 transferase is an enzyme derived from Clostridium botulinum that inactivates Rho GTPase. Because SC myelin contains MAG and PN also contains CSPGs, I tested the effects of intraocular injection of a modified form of C3 (C3-11), provided by Dr Lisa McKerracher (CONFIDENTIAL data, under IP agreement with Bioaxone Therapeutic, Montreal) on RGC axonal regeneration into PN autografts. My results showed that there was significantly more RGC survival and axonal regeneration in PN autografts after repeated intraocular injection of C3. I also tested whether intraocular injections of CPT-cAMP and/or CNTF can act in concert with the C3 to further increase RGC survival and/or regeneration. Results showed that the effect of C3 and CPT-cAMP plus CNTF were synergistic and partially additive. The use of combination therapies therefore offers the best hope for robust and substantial regeneration. The overall results from my PhD project will help determine how best to reconstruct nerve pathways and use pharmacological interventions in the clinical treatment of CNS injury, hopefully leading to improved functional outcomes after neurotrauma.
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Davidoff, Allen Warren. "Congestive heart failure in the rat." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0022/MQ31340.pdf.
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Noble, Jos Leonard Martin Louis le. "Microcirculation in the spontaneously hypertensive rat." Maastricht : Maastricht : Rijksuniversiteit Limburg ; University Library, Maastricht University [Host], 1987. http://arno.unimaas.nl/show.cgi?fid=5892.
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Jans, Sylvia Wilhelmina Sophia. "Annexin V in the rat heart." [Maastricht : Maastricht : Universiteit Maastricht] ; University Library, Maastricht University [Host], 1997. http://arno.unimaas.nl/show.cgi?fid=5915.
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Rayner, Jennifer Leigh Ball Louise M. "Atrazine and rat mammary gland development." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,516.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2006.Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment for the requirements for the degree of Doctor of Philosophy in the Department of Environmental Sciences and Engineering." Discipline: Environmental Sciences and Engineering; Department/School: Public Health.
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Brons, I. G. M. "Tissue culture of rat insulinoma cells." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303711.
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Akhtar, Sobia. "Properties of rat recombinant K+ channels." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314344.
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Cumming, D. V. E. "Nuclear protein phosphorylation in rat liver." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375227.
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Hardingham, Neil Robert. "Synaptic connections in rat visual cortex." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325298.
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