Dissertations / Theses on the topic 'Corticosterone'
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Assis, Vania Regina de. "Relação entre os níveis plasmáticos de corticosterona e testosterona no comportamento vocal e territorial no sapo martelo (Hypsiboas faber)." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-14022011-200502/.
Full textFrom studies on the endocrine control of reproductive behavior in anurans, we know that many aspects of vocal behavior and agonistic interactions of these animals are related to changes in plasma levels of testosterone and corticosterone. Among the species of neotropical frogs of great interest for studies on the endocrine control of reproductive behavior stands out Hypsiboas faber, a hylid characterized by the presence of territorial males, whose agonistic interactions cover a variety of vocal patterns with aggressiveness scale, which may culminate in physical conflict. Males of H. faber also build nests for oviposition and presents optional guard of the nests with eggs. The aim of this study was to understand the interrelationships between plasma levels of corticosterone and testosterone with calling behavior and territorial defense in males of H. faber during reproductive season. These relationships were investigated by focal observations during the vocal activities, followed by blood sampling for hormonal assay. We additionally used an experimental approach, which consisted of using recorded advertisement calls (playback), simulating an invasion of another male in the territory of the focal subjects, followed by behavioral observation and blood sampling for hormonal assay. The experimental stimulus had no effect on plasma levels of corticosterone and testosterone, neither on the majority of behavioral variables. We can identify a pattern of seasonal variation in levels of corticosterone and testosterone, as well as a positive correlation between these hormones. Additionally, individuals who vocalize at higher rates have higher levels of corticosterone during the beginning of reproductive season, while higher levels of testosterone appear in individuals more responsive to stimuli from the social environment.
Sampaio, Valdomiro de Freitas. "Efeitos da desnutrição protéica precoce e da estimulação ambiental sobre parâmetros bioquímicos e comportamentais em ratos." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/59/59134/tde-27082009-120622/.
Full textThe present study investigated the effects of protein malnutrition and environmental stimulation on the biochemical and behavioral parameters in rats. It was measured the polyamines concentration in frontal cortex, striatum and hippocampus, as well as the plasma corticosterone levels. The exploratory behavior was analyzed using the elevated plus-maze (EPM) test. Rats received either 16% (well-nourished - W) or 6% (malnourished - M) protein diets and were divided into stimulated or non-stimulated groups. Malnutrition increased corticosterone levels, decreased plasma protein content and anxiety. Non-stimulated rats tested in the EPM increased corticosterone levels, decreased hippocampal NOS activity, decreased frontal cortex, striatum and hippocampus protein and polyamines contents. Stimulation decreased open arm entries in the EPM in M animals and increased the closed arm entries in the W ones. Stimulation increased frequency and time spent in risk-assessment behaviors. These results suggest that both malnutrition and EPM testing are stressing situations as indicated by increased corticosterone levels. These results are consistent with lower anxiety and/or higher impulsiveness in M animals.
Contarteze, Ricardo Vinicius Ledesma [UNESP]. "Biomarcadores do estresse em ratos exercitados por natação e corrida em esteira rolante." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/87423.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Muitos estudos enfocando metabolismo e exercício são desenvolvidos em modelos animais, especialmente os ratos. Entre os exercícios mais utilizados nas pesquisas com animais estão a esteira rolante e a natação. Contudo, ainda persistem dúvidas de qual seria o exercício mais apropriado para desencadear mais respostas ao exercício e menos respostas associadas a outros estresses. A atividade do eixo hipotálamo-hipófise-adrenal constituído pelos hormônios ACTH e corticosterona são importantes biomarcadores de estresse. Portanto, o objetivo do presente estudo foi comparar biomarcadores do estresse durante exercício de intensidade conhecida em ratos exercitados por natação e por corrida em esteira rolante. Foram utilizados ratos Wistar adultos, adaptados aos exercícios, que tiveram a máxima fase estável de lactato (MFEL) determinada. Para isso, foram submetidos a 3 testes de 25 minutos de exercícios de natação (n=18) suportando cargas de 5,0 ; 5,5 e 6,0% do peso corporal (PC) ou 3 corridas com 25 minutos de duração (n=13) às velocidades de 15; 20 e 25 m/min. Houve coleta sangüínea da extremidade da cauda dos ratos a cada 5 minutos de exercício para dosagem de lactato. Após obtenção da MFEL, os animais foram divididos em subgrupos: (M) sacrificados imediatamente após sessão de 25 minutos de exercício (natação=09 ou esteira=07) na intensidade da MFEL ou (S) sacrificado após exercício exaustivo (natação=09 ou esteira=06) em intensidade 25% superior a MFEL. Para comparações, um grupo controle C (n=10) foi sacrificado em repouso. Utilizou-se Anova Two Way para identificar possíveis diferenças nos parâmetros de estresse (p<0,05). Foram obtidos os seguintes resultados MFEL: natação 5,5% do PC e corrida 20m/min às concentrações de lactato sanguíneo (mmol/L) de 5,2l0,3 na natação e 3,8l0,1 na corrida...
Many studies on metabolism and exercise are developed with animal models especially rats. Treadmill running and swimming are among the exercises most used in researches involving animals. However, doubts on which would be the most suitable exercise to unchain more responses to exercise and less responses associated to other stresses still remain. The activity of the hypothalamic-pytuitary-adrenal axis composed of ACTH and corticosterone hormones are important stress biomarkers. Therefore, the objective of the present study was to compare stress biomarkers during known-intensity swimming and treadmill running exercises performed by rats. Wistar adult rats previously adapted to exercises and with their maximum lactate steady state (MLSS) determined were used. To do this, rats were submitted to 3 swimming tests with 25 minutes of duration (n=18) with loads of 5.0; 5.5 and 6.0% of their body weight (BW) or to 3 running sessions with 25 minutes of duration (n=13) at velocities of 15; 20 and 25 m/min. Blood samples were collected from the tip tail of rats each 5 minutes of exercise for lactate dosage. After MLSS attainment, the animals were divided into the following subgroups: (M) sacrificed shortly after session of 25 minutes of exercise (swimming=09 or treadmill=07) at the MLSS intensity or (S) sacrificed after exhaustive exercise (swimming=09 or treadmill=06) at intensity 25% above MLSS. For comparison purposes, a control group C (n=10) was sacrificed in rest. The Two-Way ANOVA was used in order to identify possible differences in the stress parameters (P<0.05). The following results were obtained: MLSS: swimming 5.5% of the BW and treadmill running at 20 m/min at blood lactate concentrations (mmol/L) of 5.2l0.3 in swimming and of 3.8l0.1in running. Serum ACTH concentrations (pg/mL) were significantly higher for the swimming group (963.3l420.4)... (Complete abstract, click electronic address below)
Filho, Procópio Cleber Gama de Barcellos. "Efeitos da corticosterona e do estrógeno na atividade do eixo HPA de ratas: comportamento e comprimento dos telômeros." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/17/17134/tde-13092018-141304/.
Full textChronic stress promotes several changes in the functioning of an organism. Increased glucocorticoids may interfere with an individual\'s physical and psychological state. Recent works correlate chronic psychosocial stress to the reduction of the telomere length of certain cells. And estrogen, besides being a modulating factor of the activity of the stress system, can also interfere in the length of telomeres. The objective of this study was to verify if chronic exposure to glucocorticoids promotes changes in telomere length of encephalic areas involved in the control of hypothalamic-hypophysis-adrenal (HPA) axis activity and in rat behavioral responses, and whether estrogen can modulate these changes. Ovariectomized Wistar rats were treated with estradiol cypionate (50 or 100 ?g / kg, s.c.) or oil, and given 20 mg / kg corticosterone or vehicle (isotonic saline 2% Tween 80, s.c.) for 28 days. On the 25th day the animals were submitted to the forced swim test, and on the 27th day, the elevated plus maze test. On the day after the end of the hormonal treatment, the animals were euthanized for collection of blood, brain and pituitary gland. Treatment with estradiol cypionate caused: increased corticosterone and progesterone plasma concentrations; reduction of mRNA expression for CRH, AVP and POMC in PVN; an anxiolytic effect as assessed by the elevated plus maze test. A depressive effect indicated by the forced swim test; reduced size in the central amygdala and dorsal hippocampus, but not in PVN. Corticosterone caused: reduction of gonadotrophin secretion; reduction of mRNA expression for CRH and POMC and increase for AVP in PVN; a depressive effect indicated by the forced swim test. The set of results shows that changes in HPA axis activity and variation in plasma estrogen concentrations can lead to several changes in hormonal actions, behavioral activities and DNA structure in brain areas.
Long, Jennifer A. "Hormonal and Cellular Mechanisms of Fattening in Migratory Songbirds." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/LongJA2007.pdf.
Full textYang, Silei. "Rapid neuronal signaling cascades initiated by corticosterone." Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-148762.
Full textMoraes, José Evandro de. "Indicadores de bem-estar de linhagens de poedeiras comerciais leves alojadas em cinco densidades no sistema convencional de produção de ovos." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-04122018-095337/.
Full text750 commercial laying hens of white strains aged 23 weeks at the beginning of the experimental period were used, distributed in a randomized complete block design, these being characterized by the concatenation of the strains with column of cages; the treatments were five densities or stocking rates in the cage (321,43, 375, 450, 562.50 and 750 cm2/bird) with six replications, amounting to 150 experimental plots. The experimental diets were on the basis of corn and soybean meal, formulated to meet the nutritional requirements of the strains in all the phases. Both the productive and economic performances were evaluated through the weight of the eggs (g), percentage of laying (%), egg mass (g/bird/day), feed intake (g/bird/day), feed conversion per dozen (kg/dozen) and per kg of egg (kg/kg). Egg quality was determined through specific gravity (SG), Haugh units (HU), percentages of yolk, albumen and shell, shell thickness (ST), resistance to breaking (BR), yolk coloration and yolk index (YI). The welfare of the birds was evaluated through clinical, immunological and physiological indicators. For the purpose of evaluation of the results, six blocks with internal replications were established. The data were analyzed with the aid of SAS, under a mixed model, considering the effects of density, period and the interaction between them, as fixed, in addition to the random effects of block and residue. For se tratar de measures longitudinally repeated, the best covariance structure for each variable was sought. When appropriate, the Tukey-Kramer test was used for comparison of means (p<0.05). The lowest feed intake, FI/dozen of eggs and best economic performance, were obtained at the density of 321.4 cm2/bird. High housing densities did not influence the internal quality of the eggs, % shell and BR, but these variables had effects from the periods, with the best values in the early periods. High densities had negative effects on SG and ST, mainly at the laying peak of the birds. The eggs checked lie within the desired values, even at the highest densities and can be classified as of excellent quality. The housing density did not interfere (p>0.05) in the clinical evaluation of the birds, but the greater space provided in the cages of the conventional system conferred a lower frequency of lesions in the birds, indicating promotion and improvement to their general welfare. Data of heart rate and cloacal temperature were within the normal limits for the species. No differences (p>0.05) of the densities in the immune response of the birds, with the titers of the vaccine antibodies against Gumboro and Newcastle diseases above the cutoff levels were found. The treatments did not modify the blood profile of the birds and it was not possible to characterize a standard of plasma corticosterone and excretion of fecal metabolites of glucocorticoids, but the enzyme immunoassay technique, using primary antibody against corticosterone and secondary goat anti-rabbit antibody, was capable of detecting variations in the corticosterone concentrations in these tissues, however, the understanding of the meaning of these findings still requires further investigation.
Assis, Vania Regina de. "Níveis plasmáticos de corticosterona, testosterona e imunocompetência em Bufonídeos." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-14012016-151309/.
Full textGlucocorticoids modulate the immune response in complex ways in vertebrates exposed to different stressors. Given that natural populations have been exposed to a multitude of stressors, a better understanding of the functional association between duration and intensity of the stress response, the resulting changes in steroid hormone levels and their impact on different aspects of immunocompetence emerges as a cornerstone for vertebrate conservation strategies. We investigated the relationships between steroids levels and innate immunocompetence in anuran amphibians, incorporating the methodology of restraint challenge, experimental elevation of corticosterone levels by transdermal application, bacterial killing ability by spectrophotometry and the immune challenge with phytohemagglutinin. Our results demonstrate that the bacterial killing ability (BKA) measured by spectrophotometry is a reliable and accurate method to estimate the immunocompetence of anuran amphibians, additionally showed the existence of a large interspecific diversity in BKA from male anurans. When four different species of Bufonids were submitted to a restraint challenge, the general responses included increased in corticosterone plasma levels (CORT) and neutrophil/lymphocyte ratio (N:L) and decreased in testosterone plasma levels (T). The responses of BKA to restraint were much more variable, with R. icterica showing decreased and R. marina showing increased values. Additionally, CORT and N:L tended to increase more in response to restraint with movement restriction than to restraint without movement restriction, indicating that toads showed an increased stress response to the more intense stressor. All variables studied show interspecific variation. Rhinella ornate showed higher baseline CORT when compared to other species, while R. ornate and R. icterica showed the highest baseline BKA values. However, changes in N:L ratio, T levels and BKA, were not correlated to increased CORT within or between species. Transdermal application of corticosterone efficiently mimics repeated acute stress response events in Rhinella icterica, without changing the immune parameters even after thirteen days of treatment. Interestingly, long-term captivity did not mitigate the stress response, since the toads maintained three fold increased CORT even after three months under these conditions. Moreover, long-term captivity in the same condition increased total leukocyte count (TLC) and generated an even greater decrease in BKA, suggesting that consequences of the stress response can be aggravated by time in captivity. Based on our results, we consider that a careful evaluation is necessary in order to understand the modulation of the immune response by stress at intra and interspecific levels. The inclusion of different segments of the immune response is desirable, and a standardized data collection for all the species under the same period (e.g. inside or outside of breeding season) and same activity (e.g. calling or foraging) is mandatory
Barsotti, Adriana Maria Giorgi. "Modulação dos níveis plasmáticos de corticosterona e imunocompetência em resposta ao tratamento exógeno com ACTH em Hypsiboas faber." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-19032015-134658/.
Full textIn response for several stressors, the amphibian hypothalamus release the corticotrophin release hormone (CRH), which stimulates pituitary to release the adenocorticotropic hormone (ACTH) in the bloodstream. The ACTH, in your turn, acts in inter renal glands stimulating the glicocorticoids releasing, being the corticosterone the main glicocorticoid in anphibians. While the modulation exercised by the glicocorticoids of diverses physiological responses of the stress is fundamental for de maintainance of homeostasis in short period, the frequent and/or prolongued activation of the hypothamlamus pituitary interenal axis (HHI) could inhibit important process in long periods, as the reproduction and immunocompetence and affect melatonin synthesis acting directly in pineal gland. The objective of the present study was evaluate possible alterations in plasmatic corticosterone levels, testosterone, eyes melatonin levels, hematocrit and immunity aspects (Total count leucocytes and antimicrobian plasmatic capacity - against Escherichia coli) from males of the treefrog Hypsiboas faber in response to ACTH injection, as well, the temporal course of these responses. Blood and plasma samples were obtained from the 30 males captured in the field, whitin 3 minutes from the capture. The animals were transferred to the laboratory and, after two months, divided in six groups to be sampled in three different times 1 h, 3 h and 6 h after treatment. For each time one control group and one experimental group were added, receiving one injection of 105 μL of saline or ACTH solution (0,446 μg de ACTH/g of body mass (experimental group)). The ACTH treatment increase significantly the plasmatic corticosterone levels and decrease the plasmatic testosterone levels, as well, the eye melatonin levels after one hour. After six hours of the ACTH injection, occurred the increase of the hematocrit percentage and the eye melatonin levels. The ACTH treatment did not affect the immunity aspects studied in the sampling interval. The results confirm the role of the activation on the axis HHI in the inhibition of the testosterone secretion and in the modulation of melatonin secretion, althougth the possible immunomodutatory effects could happen in temporal intervals later
Sá-Rocha, Vanessa de Moura. "Aspectos neuroimunes de camundongos mantidos em uma relação social estável." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/10/10133/tde-23032007-183834/.
Full textThe objective of the present work was to investigate the repercussions of a stable social relationship on different parameters of the behavior, neurochemical and immune activity of dominant and submissives mice. Adult males (with approximately 90 days of age) kept in pairs since wean it, had been determined as dominant or submissives, after three consecutive evaluations of the behavior, where presences or absences of attacks or escapes and positions of submission had been observed. In some experiments, groups of five animals kept in one same box had been used to compare the results gotten between these and the animals coexisting in pairs. The pairs had been used only where the social hierarchy clearly was observed. The results had shown that the submissives animals in relation to the dominant ones had presented: 1) reduction in the time spent in the central zone of the open field; 2) reduction in the number of entrances in the open arms and reduction in the time spent in the exploration of the open arms of the plus maze; 3) increase in the time spent in the exploration of the closed arms of the plus maze; 4) reduction in the number of entrances and time spent in the exploration of the final third of the closed arms of the plus maze; 5) increase in the turnover of dopamine in the hypothalamus; 6) reduction in the turnover of dopamine in the corpus striatum; 7) increased number of metastasis in the lungs induced by murino melanoma experimental B16F10; 8) increase of the percentage of cells T CD8+ in the thymus after 14 days of inoculation of the same melanoma; 9) reduction in the basal oxidative burst of neutrophil and monocytes sanguine, but not in the induced by bacteria; 10) decreased NK cells activity measured in the blood and spleen. In relation to the animals kept in number of five, the submissives animals had presented: 11) reduction in the percentile of NK cells in the blood. While the dominant animals had presented in relation to the animals kept in groups: 1) increase in the turnover of norepinephrine in hypothalamus; 2) increase in the turnover of dopamine in the fluted body; 3) reduction in the percentile of NK cells in the blood. The social status, however, did not provoke differences: 1) in the absolute levels of dopamine, norepinephrine and serotonin; 2) in the metabolites of serotonin; 3) in the serum levels of corticosterone; 4) in the weight and number of cells of the spleen and thymus; 5) in the percentage of cells T CD4+ and CD8+ in the spleen and 6) in the percentage of lymphocytes, neutrophil and monocytes in the blood. Together, the results obtained had shown that dominants and submissives animals kept 90 days living in a stable social hierarchy had presented behavior and neurochemical differences, and had answered of different form to one same immune stimulation, in this case, the induced development of metastasis in the lungs for experimental melanoma murino B16F10, where the submissives had been more susceptible than the dominant ones. This results suggest that other mechanisms, different of HPA activation, may be involved with the decreased resistance of submissive mice to B16F10 tumor dissemination
Antoniassi, Julia Quilles 1991. "Influência da corticosterona em diferentes doses sobre a próstata ventral do gerbilo da Mongólia (Meriones unguiculatus) = Influence of corticosterone in diferents doses in gerbil (Meriones unguiculatus) ventral prostate." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317937.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A próstata, glândula do sistema reprodutor que tem origem embrionária a partir do seio urogenital, sendo formada por quatro pares de lobos fortemente associado à uretra: lobo anterior ou glândula coaguladora (GC), lobo dorsal (LD), lobo dorsolateral (LDL) e lobo ventral (LV). A fisiologia prostática é regulada por hormônios esteroides, principalmente andrógenos e estrógenos. Enquanto os andrógenos induzem a diferenciação, desenvolvimento, e atividade secretora, os estrógenos parecem modular os efeitos androgênicos, mantendo o crescimento e fisiologia normal da próstata. Embora o cortisol seja um hormônio largamente utilizado em medicamentos por suas ações anti-inflamatórias e imunossupressoras, pouco se sabe sobre os efeitos colaterais desses medicamentos, principalmente na morfofisiologia prostática. Além disso, sabe-se que esse hormônio está altamente relacionado com o estresse e com alguns distúrbios de comportamento. Desta forma, este projeto visou avaliar, por métodos histológicos, histoquímicos, imunocitoquímicos e estruturais com parâmetros qualitativos e quantitativos, diversos aspectos morfofuncionais da glândula prostática ventral de machos de gerbilo (Meriones unguiculatus), após a aplicação por cinco dias de corticosterona em duas doses diferentes: 0,5mg/kg/dia e 1,5mg/kg/dia, além disso os grupos foram subdivididos em um grupo com um período de 5 dias de descanso após o tratamento e outro grupo que foi morto um dia após o fim do tratamento. Os dados apresentados mostram que a corticosterona possui propriedades antiproliferativas e antiapoptóticas sobre a próstata de gerbilos. Esse hormônio também alterou a frequência dos receptores dos principais hormônios reguladores desse órgão, como andrógenos e estrógenos. Em relação aos receptores de glicocorticóides (GR), foi observada uma redução da sua expressão quando a concentração sérica da corticosterona encontrava-se elevada. As alterações na expressão dos receptores supracitados levaram ao surgimento de displasias prostáticas importantes. Houve uma variação nos efeitos desencadeados por esse hormônio de acordo com a dose aplicada, sendo que uma maior dose apresentou efeitos mais discretos e uma menor dose mostrou ser mais impactante. Os efeitos da corticosterona nos receptores nucleares foram revertidos ou atenuados após o período de descanso, o que não foi observado para os padrões de proliferação e apoptose celular
Abstract: The prostate, gland of reproductive system, has embryonic origin from the urogenital sinus and consists four lobes that are strongly associated with the urethra: anterior lobe or coagulating gland (CG), dorsal lobe (LD), dorsolateral lobe (LDL) and ventral lobe (LV). Steroid hormones, mainly androgens and estrogens, regulate the prostate physiology. While androgens induce differentiation, development and secretory activity, estrogens appear to modulate androgen effects, maintaining normal growth and prostate physiology. Although cortisol is widely used in drugs because their anti-inflammatory and immunosuppressive actions, little is known about the side effects of these drugs, especially in the prostate morphophysiology. Furthermore, it is known that this hormone is highly correlated with stress and some behavioral disorders. Thus, this research aimed evaluate, by histological methods, histochemical, immunocytochemical with structural and qualitative and quantitative parameters, various morphological and functional aspects of the ventral prostate gland of male gerbil (Meriones unguiculatus) after application of corticosterona. This hormone was applicated for five days with two doses of corticosterone: 0.5mg/kg/day and 1.5mg/kg/day, in addition, the groups were divided into a group with a 5-day period of rest after the treatment and another group was killed one day after the end treatment. The data showed that corticosterone has antiproliferative and anti-apoptotic properties on the prostate gerbils. This hormone also changed the frequency of AR, ER?, ER? e GR. We observed a reduction of glucocorticoids receptors expression when serum concentration of corticosterone was elevated. These changes led to the emergence of important prostatic dysplasia. There was a variation in effects triggered by this hormone in accordance with the applied dose, being that a higher dose reported effects more discrete and a lower dose was shown to be more impactful. The effects of corticosterone on nuclear receptors have been reversed or attenuated after rest period, which was not observed for apoptosis and cell proliferation patterns
Mestrado
Biologia Celular
Mestra em Biologia Celular e Estrutural
Crowgey, Erin Lynn. "Effects of protein malnourishment and corticosterone on thymocyte apoptosis." Connect to this document online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1134141732.
Full textTitle from first page of PDF document. Document formatted into pages; contains [1], iv, 44 p. : ill. Includes bibliographical references (p. 40-44).
Ebada, Mohamed Elsaed Elsayed. "The rewarding and cognitive effects of corticosterone in mice." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/12677/.
Full textLindroth, Linnéa. "The relationship between corticosterone and personality in red junglefowl." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166675.
Full textMehta, Devanshi M. "The importance of diurnal corticosterone rhythms in regulating mood." Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent1564147320606141.
Full textOskarsson, Viktoria. "How does variation in corticosterone relate to animal personality?" Thesis, Linköpings universitet, Biologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-150526.
Full textHatore, Edgar Teruhiko. "Efeito da intensidade do estresse sobre marcadores metabolicos." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314621.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Os efeitos do estresse por natação sobre marcadores metabólicos diferem daqueles do estresse por choques nas patas. Estas diferenças poderiam ser conseqüências da natureza do estressor, que difere nos dois modelos, ou da intensidade de estresse, que parece ser menor quando os animais são submetidos à natação do que quando submetidos a choque nas patas. O objetivo deste trabalho é avaliar o efeito da intensidade do estressor sobre a mobilização de substratos metabólicos. Ratos Wistar adultos foram distribuídos em grupos: controle, não submetido à natação; e ratos submetidos à natação em água a 35°C, 24°C ou 18°C. As sessões de natação ocorreram em três dias consecutivos com 5, 15 e 15 min de duração, respectivamente. Os ratos foram pesados antes da primeira e da última sessão de natação e após a última sessão sua temperatura retal foi determinada por um tele-termômetro; foram anestesiados e uma amostra de sangue foi coletada por punção cardíaca. Foram retiradas amostras do fígado e dos músculos gastrocnêmio, sóleo e ventricular cardíaco. Adipócitos foram isolados do tecido adiposo epididimal e incubados com agonistas adrenérgicos. O glicerol e o lactato liberados no meio infranadante foram considerados como indicadores da sensibilidade das respostas lipolítica e glicolítica aos agonistas, respectivamente. Foram determinadas também as concentrações plasmáticas de glicose, lactato, ácidos graxos livres, glicerol e corticosterona, além da concentração muscular e hepática de glicogênio. O peso corporal dos ratos dos quatro grupos não apresentou diferença estatisticamente significativa antes da primeira ou da terceira sessão de natação. Após natação em temperaturas de 24°C e 18°C os ratos apresentaram hipotermia (30,7 +/- 0,7°C e 24,0 +/- 0,5°C, respectivamente) em relação os grupos controle (37,2 +/- O,12°C) e natação a 35°C(36,7 +/- 0,2°C), entre os quais não houve diferença estatisticamente significativa. Após a terceira sessão de natação, a concentração plasmática de corticosterona aumentou significativamente nos grupos submetidos à natação em 18°C (294,7 +/-17,9 ng/mL) e 24°C (289,5 +/- 27,1 ng/mL) do que 35°C (166,3 +/- 11,8 ng/mL), sendo os três significativamente diferentes do controle (57,2 +/- 10,0 ng/mL), enquanto que as concentrações sanguíneas de lactato e de ácidos graxos livres estavam significativamente elevadas em relação ao controle, mas não diferiram entre os grupos de ratos submetidos à natação. As concentrações de glicogênio das amostras hepáticas, cardíacas e do músculo sóleo de ratos submetidos à natação não diferiram significantemente do grupo controle. Porém, as concentrações de glicogênio nas porções branca e vermelha do músculo gastrocnêmio estavam reduzidas após natação. Em adipócitos isolados de ratos submetidos à natação houve aumento da liberação basal de glicerol e de lactato, mas as respostas ao d-butiril-AMPc, à noradrenalina e à adrenalina, assim como a sensibilidade às duas catecolaminas,não diferiu significantemente do controle. Concluímos que a intensidade do agente estressor pode ser modulada pela temperatura da água em protocolos de estresse por natação, de modo que as temperaturas mais baixas em relação à temperatura corporal do rato determinam respostas de estresse mais intensas, evidenciadas pela concentração plasmática de corticosterona. Entretanto, as alterações observadas nos marcadores metabólicos analisados são independentes da intensidade do estressor, no paradigma de estresse utilizado neste trabalho
Abstract: The effects of swimming stress on metabolic markers are different than those induced by foot-shock stress. These differences might be due either to stress intensity, which seems to be minor when the rats are submitted to swimming than foot-shock stress, or to the type of stressor agent. The aim of this work is to evaluate the effect of the stressor intensity on metabolic markers. Adult Wistar rats were distributed in groups: control, not submitted to swimming; or swimming stressed rats with the water temperature at 35°C, 24°C or 18°C. Swimming sessions occurred daily, for 3 days, with 5, 15 and 15 min duration, respectively. Before the first and last sessions the rats were weight and after the last swimming session the rat's rectal temperature was determined using a tele-thermometer; then the rats were anesthetized and a blood sample was collected through cardiac puncture. Samples of the liver, as well as the gastrocnemius, soleus and cardiac muscles were also collected. Adipocytes were isolated from the epididimal adipose tissue and were incubated with adrenergic agonists: The glycerol and lactate released in the infranatant were considered as indicative of in vitro lipolytic and glycolytic sensitivity to the agonists,respectively. The plasma concentrations of glucose, lactate, free fat acids, glycerol and corticosterone, as well as the muscular and hepatic glycogen concentrations were determined. The results have shown that the rat' s body weights were not altered by swimming. After swimming at 24 C and 18 C the rats showed severe hypothermia (30.7+/-0.7°C and 24.0+/- 0.5 C, respectively, p<0.05), whereas swimming at 35C did not alter the rats rectal temperature (36.7 +/-0.2°C) compared to control (37.2 +/- 0.12C). The plasma levels of corticosterone significantly enhanced in 18°C (294.7 +/- 17.9 ng/mL), 24°C (289.5+/- 27.1 ng/mL) and 35°C (166.3 +/-11.8 ng/mL) swimming groups, compared to control (57.2 +/- 10.0 ng/mL). The glucose and glycerol plasma levels were not altered, whereas the blood lactate and free fat acids levels significantly increased after swimming, with no difference between the stressed groups. Swimming did not alter the glycogen concentrations of the liver as well as cardiac and soleus muscle, but caused a decrease in the white and red gastrocnemius compared to control, with the decrease being independent of the water temperature. The in vitro basal glycerol and lactate release by adipocytes increased, similarly in all swimming groups. The lipolytic response to d-butiryl cAMP,norepinephrine and epinephrine were not different between groups. Catecholamines determined a biphasic effect on lactate release by adipocytes with the concentrations in the range up to 10 nM being stimulant and those higher than 10 nM being inhibitory of lactate release. No differences were observed between groups. We conclude that the stress intensity might be modulated by the water temperature in protocols of swimming stress, with lower temperatures being more stressful than those similar to the rats body temperature, as determined by the plasma levels of corticosterone. We also conclude that the swimming stress paradigm altered the analyzed metabolic markers in a manner that was independent of the stressor intensity (homotypic), in the stress paradigm used in this work
Mestrado
Fisiologia
Mestre em Biologia Funcional e Molecular
Camin, Nathália de Azevêdo. "Controle do sistema de estresse em ratas Wistar adultas submetidas ao bloqueio dos receptores mineralocorticoide ou glicocorticoide após estresse na pré-puberdade." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/17/17134/tde-29032017-165315/.
Full textAdolescence is a critical period to the individual\'s development. Several brain structures responsible for the control of stressful responses reach maturity during this phase. Thus, acute or chronic stressors can have a negative effect and alter the stress response as well as behavior in adulthood. The hypothalamus-pituitary-adrenal axis (HPA) is part of the stress system, whose inhibitory control is regulated by glucocorticoids through mineralocorticoid (MR) and glucocorticoid (GR) receptors. It is unknown the role of these receptors in the long-term effects induced by stress in the prepuberty in animals models. The aim of this study was determine whether MR or GR receptor blockade after stress in prepuberty prevents their changes on exploratory behavior and control of the HPA axis in adult female rats. Thus, prepuberty female rats, at 26 days old, were submitted to one or seven daily restraint sessions followed by administration of MR (Spironolactone) or GR (RU-486) antagonists. In adulthood, at 60 days old, the animals were evaluated in the elevated plus maze. In the next day, they were subject again to restraint concurrently with serial blood sampling to evaluate the HPA axis response. Subsequently, it was performed the brain perfusion as well as the collection of the adrenal glands and thymus. It was conducted the dosage of corticosterone by radioimmunoassay and analyzed the expression and activity of CRH neurons in the medial parvocellular subdivision of the paraventricular nucleus of the hypothalamus by immunohistochemistry. Chronic stress in prepuberty reduced the body weight, delayed the puberty and decreased the CRH and Fos expression in response to acute stress in adulthood. There was no effect on thymus weight and behavioral parameters. However, RU-486 increased the corticosterone secretion and adrenal glands weight. Acute stress caused advancement of puberty and associated with RU-486 or Spironolactone also reduced the activity of CRH neurons in response to the same stressor in adulthood. These results demonstrate that Spironolactone administration may be a promising strategy to attenuate the central long-term effects resulting from acute stress in prepuberty.
Monteiro, Stefanny Christie Gomes. "Relações entre taxa de vocalização, níveis plasmáticos de corticosterona e imunocompetência em Hypsiboas albopunctatus (Spix, 1824)." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-10102013-152930/.
Full textAccording to the model of intersexual selection mediated by parasites, changes in conditions of sexual ornaments or display rates reflect different degrees of resistance to parasitism. In natural choruses of amphibians, calls that are higher, longer, more complex and / or issued at higher rates are probably more easily detected and attract more females. However, the vocal effort is positively related to plasma levels of potentially immunosuppressive steroids, such as testosterone and corticosterone. The aim of this study was to evaluate the relationship between calling rates, immunocompetence and plasma levels of corticosterone in Hypsiboas albopunctatus, a midsize anuran occurring in South America. Such relationships were studied from focal observations of calling behavior, followed by blood collection for measurements of corticosterone plasma levels and evaluation of some immune parameters. The present study showed a positive relationship between the calling rate with plasma levels of corticosterone, and a negative correlation between these two parameters with cell-mediated immunocompetence. These results highlight the importance of the hormone corticosterone as a possible mediator of trade-off between vocal effort and cell-mediated immunity in anurans.
Madelaire, Carla Bonetti. "Relação sazonal entre reprodução, energética e imunocompetência em sapos da Caatinga." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-16042018-133637/.
Full textWe investigated the correlation between imunological parameters, steroid plasma levels in 3 anuran species during different life history stages (Chapter1). Chapter 2 explore the seasonal adjusments of metabolic regulators for 3 anuran species. In the 3th chapter, we studied the casual relationship between increase of steroid plasma levels and immunomodulation in males of Rhinella jimi. Additionally, w e investigated the metabolic cost of the immune response, standard metabolic rate, and steroid plasma levels of R. jimi (Chapter 4). Our results point to an opposite direction of the immunocompetence handicap hypothesis (Chapter 1 and 4), high steroid plasma levels are associated to higher immune response. The results found in the chapter 3 corroborates the immunomodulatory effects of testosterone and corticosterone. Chapter 2 shows the seasonal variation of metabolic regulators, which guarantee muscle and cellular maintenance during the dry period for all three species. The aestivating species activates pathways that shut down ATP consumption saving energy during the drought
Gagliano, Humberto Antonio. "¿Puede el metilfenidato atenuar el impacto del estrés? un modelo experimental en rata." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/382629.
Full textPrevious studies evidenced in rats that amphetamine administration immediately after the exposure to different stressors decreases the activation of the hypothalamic-pituitary-adrenal axis (HPA), as well as the hyperglycemia (index of activation of the sympathetic medullary adrenal axis) caused by exposure to stress. The effect is located at the CNS level. The purposes of the present Thesis have been to extend the study of the interaction between stress and amphetamine and specially to demonstrate that methylphenidate (MPH), the most used stimulant in the treatment of the attention deficit- hyperactivity disorder (ADHD), is also able to reduce, at relevant therapeutic doses, the biological and behavioral response to emotional stress. The studies have been conducted in male adult rats (2-3 months of age), except in one experiment aimed to compare the effects of MPH in young and adult animals. Results with amphetamine indicate, in agreement with previous data, that the drug reduces in a dose-dependent way, the physiological response to the forced swim. But, moreover, this negative interaction between both stimuli also acts in the opposite manner, in a way that the exposure to stress reduces the HPA activation caused by amphetamine. In a series of experiments conducted with MPH we have demonstrated that the drug by itself does not modify the HPA axis, but, in the same way than amphetamine, is able to reduce the physiological response to stress (forced swim) when the drug is given immediately before stress. The effect is evidenced at the CNS level (CRF gene expression, the main factor that regulates the HPA axis), is observed in both young and adult animals and it is also detected when the drug is administered 30 min before exposure to stress. The protective effects of MPH are observed not only at the physiological level but also at the behavioral level in a two-way active avoidance/escape task, with an improvement in the learning and with lower levels of contextual fear conditioning. All together, the results show, for the first time, a protective effect of MPH in front of the effects of stress, having important clinical implications.
Wilder, Sarah A. "The Relationships between Energetic Condition, Immune System Cellular Components, Testosterone Corticosterone, and Hemoparasites in Breeding Birds." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/WilderSA2007.pdf.
Full textRoberts, Veronica J. "Corticosterone modulation of noradrenaline stimulated cyclic AMP formation in hippocampus." Thesis, University of Ottawa (Canada), 1985. http://hdl.handle.net/10393/4949.
Full textFish, Eric W. "GABAA positive modulators, corticosterone, and schedule heightened aggression in mice /." Thesis, Connect to Dissertations & Theses @ Tufts University, 2003.
Find full textAdvisers: Klaus Miczek; Joe DeBold. Submitted to the Dept. of Psychology. In title, GABAA is spelled GABA with a subscript A. Includes bibliographical references (leaves 146-183). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
Verkuyl, Jan Maarten. "Stress, corticosterone and GABAergic inhibition in the rat paraventricular nucleus." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2003. http://dare.uva.nl/document/70710.
Full textKyle, Catriona Jane. "Contributions of cortisol and corticosterone to metabolic regulation in humans." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33042.
Full textKulp, Adam. "THE ROLE OF CORTICOSTERONE AND IL-1β ON FEAR MEMORY." Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent1568766796672602.
Full textLee, Huk-kai Paul. "Corticosteroid effects on serotonergic function : a study on the acute and chronic effects of corticosteroids on serotonin uptake and binding in rat synaptosomes and blood platelets /." [Hong Kong : University of Hong Kong], 1985. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12315163.
Full textSiqueira, Camila Silva. "Influência da adrenalectomia bilateral nos eventos neurodegenerativos no modelo do parkinsonismo experimental pela 6-OHDA nigral. Enfoque aos mecanismos parácrinos gliais envolvidos na neuroproteção e cicatrização." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/47/47135/tde-17122009-084533/.
Full textThis study has the objective to evaluate the effect of the bilateral adrenalectomy in the neurodegenerative process and cicatrization on the nigroestriatal pathway injury through 6-hydroxydopamine (6-OHDA) in rat, and in this way contribute for the interpretation of the adreno esteroides hormones effects in the neurodegenerative and neurotrophics process in the central nervous system.injury Adult rats wistar were submitted in a surgery to take the bilateral adrenal gland or a simulate surgery of the same. After 2 days the animals was involved into a stereotaxic surgery to nigroestriatal dopaminergic lesion with a unilateral injection of the 6-OHDA in the nigra. The animals received daily corticosterone hormonal (10mg/kg) or vehicle solution. After a period of 72 hours, 1 week and 3 weeks, the animals were decapitated, and the regions of the ventral midbrain and striatum it was bilaterally dissected. The tissue was processed by Western blot method and analyzed for the following markers: tyrosine hydroxylase (TH - enzyme that join of the dopamine conversion pathway), glial fibrilar acid protein (GFAP protein of the intermediary filament of the astrocyte citoesqueleto, the moleculars extracellular matrix phosphacan, neurocan, chondroitin sulfate and NG2, the Laminin protein and finally, the neurotrophic factor (FGF-2) in the region of ventral midbrain, where watched trophic actions in the dopaminergic neurons that could have effects in the inflammatory processes by your gliogenic and angiogenic actions. In this way, the dopaminergic neurodegeneration was evaluated by the TH levels, the astrocytary activation by the GFAP levels, the cicatrization processes by the molecules regulation of the extracellular matrix and the trophics FGF-2 answers. By the results it is possible that adrenal glucocorticoid hormones modulate the elements involved in neurodegeneration, repair and cicatrization of the dopaminergic system.
Ribeiro, Gisele Silva. "Estudo estrutural e bioquímico da bexiga de ratos após tratamento com altas doses de corticosterona." Universidade do Estado do Rio de Janeiro, 2010. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=3846.
Full textO objetivo deste trabalho foi analisar as alterações estruturais e bioquímicas na parede da bexiga resultante do tratamento crônico de ratos pré-púberes com altas doses de corticosterona. Foram estudados 26 ratos Wistar divididos em quatro grupos: T30 foi tratado com corticosterona até 29 dias de idade e morto no dia 30. T65 recebeu o mesmo tratamento, mas foi morto com 65 dias. Cada grupo tinha seu próprio controle (C30 e C65). Os animais foram tratados com injeções intraperitoneais diárias de corticosterona (2 mg/100g peso corporal) entre o 7 e 29 dias de vida. A bexigas foram removidas e processadas para inclusão em parafina. Foram estudados os seguintes elementos da parede vesical: Colágeno, músculo liso, fibras do sistema elástico, densidade vascular e do epitélio. Estes parâmetros foram analisados por métodos morfométricos, imunofluorescência e bioquímica. A densidade vascular na lâmina foi reduzida em 40% (p <0,05) no grupo T65. A organização do colágeno foi alterada em T30 e T65, apesar da concentração de colágeno total não ser alterada. O grupo T65 teve um aumento de fibras do sistema elástico. Não houve diferença na altura e na densidade de células epiteliais entre os grupos. Quanto à densidade de fibras musculares lisas, observamos um aumento de 19% (p <0,05) no grupo T65. A administração de corticosterona na fase pré-púbere provoca modificações estruturais na bexiga de ratos afetando de modo significativo o substrato morfológico sob qual repousa a fisiologia vesical. Foi observado também que estas modificações normalmente aparecem num tempo mais longo após o término do tratamento
The aim of this work was to analyze the structural and biochemical changes on the bladder wall resulting from the chronic treatment of prepubertal rats with high doses of corticosterone. This study included 26 male Wistar rats assigned to four groups: T30 was treated with corticosterone until 29 days of age and killed at day 30, while T65 group received the same treatment but was killed at day 65. Each group had its own control group (C30 and C65). For treated animals, daily intraperitoneal injections of corticosterone (2 mg/100g body weight) were administered between 7th and 29th day of life. Bladders were removed and collagen, smooth muscle, elastic fibers system, vascular density and epithelium were analyzed by morphometrical methods, immunofluorescence, and biochemistry.Vascular density in lamina propria was reduced by 40% (p<0.05) in group T65. Collagen organization was altered in T30 and T65, although total collagen concentration was unchanged. The T65 group had an increase in elastic system fibers. There was no difference in epithelial height and cell density between the groups. Concerning the smooth muscle fibers density we observed a 19% increase (p<0.05) in the T65 group. Our results show that prepubertal administration of corticosterone induces structural modifications in the bladder of rats
Sanders, Sarah K. "Ethanol exposure during early infancy effects on intake, tolerance and corticosterone /." Diss., Online access via UMI:, 2005.
Find full textMurray, John Fraser. "Biochemical, behavioural and cellular studies of chronic antidepressant and corticosterone administration." Thesis, University College London (University of London), 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429139.
Full textGubba, Elizabeth Mary. "Trophic effects of corticosterone and dehydroepiandrosterone on the cultured rat brain." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621390.
Full textBlandino, Peter. "Regulation of neuroinflammation during stressor exposure roles for norepinephrine and corticosterone /." Diss., Online access via UMI:, 2008.
Find full textSmithson, Jacqueline Louise. "The effects of corticosterone on persistence of attention in Mus Musculus." Thesis, Keele University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.716859.
Full textOrtolani, Daniela. "Efeitos de dieta palatável sobre a resposta de estresse em ratos." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314637.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Tem sido proposto que o acesso a alimentos palatáveis atenua a resposta de estresse. O objetivo deste estudo foi examinar o efeito de uma dieta palatável sobre parâmetros comportamentais e hormonais de ratos submetidos a estresse por choque nas patas. Ratos controles e estressados preferiram dieta palatável à comercial e a diminuição da ingestão alimentar induzida pelo estresse foi abolida em ratos com acesso a dieta palatável. Como conseqüência das diferenças de ingestão alimentar entre os grupos, ratos estressados e alimentados com dieta comercial consumiram quantidade inferior de calorias quando comparados com os controles, enquanto que ratos com acesso a dieta palatável ingeriram quantidade maior de calorias, não sendo alterado pelo estresse. Apesar dessas diferenças o peso corporal não se alterou. Ratos submetidos ao estresse aumentaram o número de entradas e o tempo de permanência no braço aberto do labirinto em cruz elevado (LCE), e também o número de imersões de cabeça. O número de estiramentos e de avaliações de risco foi diminuído pelo estresse por choque nas patas. A dieta palatável também diminuiu o número de avaliações de risco. Os animais submetidos ao estresse e com acesso ao alimento palatável apresentaram maior latência para o primeiro cruzamento e permaneceram mais tempo no centro do campo aberto. O número de levantamentos avaliado no campo aberto aumentou com a ingestão de dieta palatável, e o número de cruzamentos, auto-limpezas e bolos fecais não foi alterado pelo estresse nem pela composição da dieta. O aumento da concentração sérica de corticosterona induzido pelo estresse foi atenuado pela ingestão de dieta palatável. O estresse aumentou as concentrações de glicose e de insulina, e diminuiu as concentrações de triacilgliceróis. O consumo de dieta palatável aumentou a concentração de glicose, de leptina e de triacilgliceróis. Esses resultados mostram que o estresse reduz a ingestão alimentar e que esta redução é prevenida pelo acesso a dieta palatável. Este protocolo de estresse induziu à diminuição da ansiedade, com atenuação da concentração de corticosterona pelo alimento palatável. A combinação de dieta palatável e estresse afeta parâmetros metabólicos que podem levar à resistência a insulina. O efeito anorexigênico do estresse aconteceu independente da concentração de leptina, portanto outros fatores devem estar envolvidos com o controle do comportamento alimentar, como por exemplo, CRF e outros peptídeos, devendo ser estudados neste modelo experimental.
Abstract: It has been proposed that the access to palatable foods attenuates the stress response. The aim of this study was to examine the effect of a palatable diet on behavioral and hormonal parameters of rats submitted to footshock stress. Both control and stressed rats preferred the palatable than commercial diet and the stress-induced decrease in food intake was abolished in rats with access to palatable diet. As a consequence of the differences in food intake between the groups, rats submitted to stress and fed with commercial diet consumed a lower amount of calories than control rats, whereas rats with access to palatable diet ingested a higher amount of calories that was not altered by stress. Despite these differences, the body weight not altered. Rats submitted to stress increased the number of entries and the time spent in the open arms in the elevated plus maze (EPM), and also the number of head dipping. The number of stretched-attend posture and the risk assessment were decreased by footshock stress. The palatable diet also decrease the number of risk assessment. The rats submitted to stress with access to palatable diet showed a higher latency to the first crossing, and spent more time in the centre in the open field. The number of rearing increased with palatable diet intake, and the number of crossing, grooming and fecal bolus were not altered by stress neither diet composition. The stress-induced increase in serum corticosterone concentration was attenuated by palatable diet. The stress increased the serum glucose and insulin concentrations, and decreased the triacylglycerols concentrations. The access to palatable diet increased the glucose, leptin and triacylglycerols concentrations. These results showed that the stress reduces the intake food and that this reduction is prevented by access to palatable diet. This protocol of stress induced less anxiety-like behaviors with attenuation of corticosterone concentration induced by palatable diet. It is concluded that stress associated with palatable diet intake affect metabolic parameters that may lead to insulin resistance. Moreover, footshock stress had an anorexigenic effect that was independent of leptin, therefore other factors involved with the control of feeding behavior, such as CRF or other peptides, must be investigated in this experimental model.
Mestrado
Fisiologia
Mestre em Biologia Funcional e Molecular
Honda, Bruno Takashi Bueno. "Avaliação dos efeitos do estresse por calor sobre a atividade de linfócitos e a resposta vacinal ao paramixovírus (Doença de Newcastle) em frangos de corte." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/10/10133/tde-19112013-151532/.
Full textA number of factors, such as environment, nutritional status and diseases are stressful for animals during livestock production. It has been shown that broilers exposed to stressors for prolonged periods tend to present decreased weight gain and feed intake and to have an increased feed conversion ratio, increase mortality rate and predisposition to diseases caused by secondary agents. Vaccination is an essential practice for adequate management of the livestock and protection of poultry against bacterial and viral infectious agents. Understanding the factors that modify the success vaccination is essential for optimizing animal health and welfare, thus allowing them to use of all the genetic and nutritional potential they have. Few studies have emphasized the effects of heat stress on cellular and humoral broilers immunity. This study aimed at discussing the effects of heat stress on cellular immunity (B and T lymphocytes) and humoral immunity (IgM and IgY) of broilers undergoing a vaccination protocol for Newcastle disease (LaSota strain). For this purpose, 96 male broilers (Cobb) were random divided into four groups: 1. Unvaccinated broiler chickens exposed to thermoneutral temperature; 2. Vaccinated broiler chickens exposed to thermoneutral temperature; 3. Unvaccinated broiler chickens exposed to a heat stress protocol (38±2°C). 4. Vaccinated broiler chickens exposed to a heat stress protocol (38±2°C). All broilers were housed in isolators and provided water ad lib. We used a live Newcastle vaccine disease virus of LaSota strain given in two doses at 7 and 14 days. The broiler chickens were exposed to heat stress (38±2°C) from the 2nd to 6th day of life. It has been observed that when combined with the vaccination challenge, heat stress was able to change immune cells profile from a B to T cytotoxic and T helper immune cells, keeping this change pattern until the end of the study period (over 19 days). This change in the cellular response pattern modified the ability of the broiler chickens´ immune system to react while challenged by vaccination, reducing its efficiency and making them more susceptible to the disease agent. The data obtained suggest that heat stress by itself induced considerable modifications in the liver, spleen and bursa de Fabricius and induced a significant modification in the profile of immune cells in peripheral blood of birds, with responsive modifications in the pattern of immunoglobulins, directly influencing the response of the broilers against the environmental challenge (when the stress is evaluated separately) or the vaccination (when the stress is measured along the challenge vaccination with Newcastle Disease virus). Therefore, we suggest that the heat stress was capable of reduce the efficacy of the vaccinal response in broiler chickens, related to the modification of the lymphocytes and the production of immunoglobulins.
Horton, Brent. "Corticosterone and Morph-Specific Variation in the Reproductive Behavior of the Polymorphic White-Throated Sparrow (Zonotrichia albicollis)." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/HortonBM2007.pdf.
Full textWentworth-Eidsaune, Christine L. "Short-Term Administration of Corticosterone has Lasting Effects on Learning in Young Rats." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1277133963.
Full textJuneau, Véronique. "Chronically Elevated Corticosterone Levels, via Cocoa Butter Injections of Corticosterone, Do Not Affect Stress Response, Immune Function, and Body Condition in Free-living Painted Turtles (Chrysemys picta)." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31817.
Full text李克楷 and Huk-kai Paul Lee. "Corticosteroid effects on serotonergic function: a study on the acute and chronic effects of corticosteroids onserotonin uptake and binding in rat synaptosomes and bloodplatelets." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1985. http://hub.hku.hk/bib/B31230519.
Full textQiu, Guang, and 邱光. "Assessment of the role of corticosterone and adiponectin in the neuroprotective effect of dietary restriction." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41290604.
Full textQiu, Guang. "Assessment of the role of corticosterone and adiponectin in the neuroprotective effect of dietary restriction." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41290604.
Full textSchildkraut, Rachael. "Characteristation of positive welfare indices in captive african lions (Panthera leo)." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/16739.
Full textBruneli, Frank Angelo Tomita [UNESP]. "Concentrações plasmáticas de estradiol, testosterona, progesterona, prolactina e corticosterona em perdizes (Rhynchotus rufescens), criadas em cativeiro." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/104930.
Full textConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Sob condições de estresse, as aves apresentam, como resposta corporal, uma série de alterações metabólicas e hormonais a fim de se adaptar às agressões do meio. Para estabelecer a associação das concentrações plasmáticas de corticosterona e prolactina com a característica indicativa de estresse, foram avaliados 21 machos e 22 fêmeas de perdizes (Rhynchotus rufescens) alojados em um galpão avícola convencional. De cada ave, foram efetuadas três medições matinais do tempo de permanência em imobilidade tônica, a intervalos de sete dias. Adicionalmente, foram colhidas amostras sanguíneas de aproximadamente 2,0 mL, através da punção da veia braquial, com seringa descartável heparinizada de 3 mL e agulhas 25x7 mm, 15 dias antes da primeira medição do tempo em imobilidade tônica (final de junho), e 3 dias após a última medição (final de julho). As informações prévias sobre produção de ovos pelas fêmeas e fecundação de ovos pelos machos de perdizes, obtidas durante a estação reprodutiva 2002-2003, foram utilizadas para classificação das aves conforme o desempenho produtivo em cativeiro. Nenhum dos efeitos testados para corticosterona foi significativo, em cada um dos sexos. No curto período de 30 dias, houve significativa redução da prolactina circulante no sangue, sendo que os machos variaram de 5,77 a 3,95 ng/mL, enquanto as fêmeas reduziram de 6,03 para 4,44 ng/mL. Não foi encontrada correlação significativa (P>0,05) entre quaisquer das características avaliadas no presente trabalho, tanto em machos quanto em fêmeas. O tempo de permanência em imobilidade tônica não foi indicativo do estado de estresse em perdizes criadas em cativeiro.
In many stress conditions, birds presents an organic response with a series of metabolic and hormonal alterations, to become accustomed to environmental agressions. The objective of this study was to associate corticosterone and prolactin plasmatic concentrations with a indicative stress characteristic, evaluating 21 post-breeding partridge males and 22 post-breeding partridge females (Rhynchotus rufescens) carried out in a conventional avian barn. One time per week, during three consecutives weeks, mensurations of tonic immobility response were made in the morning. In addition, blood samples about 2.0 mL were collected via brachial vein punction, using anticoagulating sirynge and 25x7 mm needles, 15 days before first tonic immobility mensuration (end of june-2003), and again three days after last mensuration (end of july-2003). Previous informations about female egg production e male egg fertilization, during 2002-2003 breeding season were used to bird classification by productive performance in captivity. None of effects tested to corticosterone secretion was significative in any sex. Although in a short time period, 30 days approximately, prolactin concentration significative reduced in blood circulation, where males declined from 5.77 to 3.95 ng/mL, and females declined from 6.03 to 4.44 ng/mL. No correlation was find significative (P>0.05) among any evaluated characteristics, for both sexes. Tonic immoblility response was not a stress determination to partridges raised in captivity.
Grego, Kathleen Fernandes. "Determinação dos níveis séricos de corticosterona e hormônios esteróides sexuais, induzidos pelo estresse da contenção física e da extração de veneno, em Bothrops jararaca (Ophidia: Viperidae)." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/10/10133/tde-02032007-120212/.
Full textIn the present studies, 30 snakes of the species B. jararaca with three years old, born in captivity at the Laboratório de Herpetologia - Instituto Butantan - were divided into 3 experimental groups, each one containing 10 animals. The mean weight and snout vent length of males and females were 97 grams and 75 centimeters and 281 grams and 99 centimeters, respectively. The Group A animals did not have their daily management modified since their birth, staying at the same room through all experiment. The Groups B and C animals were transferred, at the beginning of the studies, to the same venom extraction room, but only snakes of Group C were submitted to milking routine. Each two months for a period of a year 2 ml of blood were collected by ventral caudal venipuncture, at two different moments, for hematological exams and serum measurement of estradiol, testosterone and corticosterone by RIA (radioimmunoassay). The first blood samples were collected 120 seconds after physical restraint and the second blood samples occurred 90 minutes after physical restraint and/or milking routine. Snakes of the three groups showed high serum levels of corticosterone response for the restraint and/or milking procedure, indicating that these procedures can be considered stress agents. Although it has not been observed a significant correlation between levels of corticosterone and sexual steroids hormones, testosterone concentration in males and estradiol concentration in females diminished in animals showing higher levels of corticosterone. The heterophil/limphocyte relation could not be considered a good stress indicator in pitvipers of our studies.
Schmidt, Kimberly L. "Cortisol and corticosterone in the immune system and brain of developing songbirds." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/5373.
Full textYang, Silei [Verfasser], and Rainer [Akademischer Betreuer] Landgraf. "Rapid neuronal signaling cascades initiated by corticosterone / Silei Yang. Betreuer: Rainer Landgraf." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2012. http://d-nb.info/1027066143/34.
Full textWant, Elizabeth Joy. "The investigation of corticosterone metabolism in a rat model of alcohol toxicity." Thesis, King's College London (University of London), 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429280.
Full textNamvar, Sara. "Investigating the role of corticosterone in meal anticipatory behaviour, metabolism and glucosetolerance." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/investigating-the-role-of-corticosterone-in-meal-anticipatory-behaviour-metabolism-and-glucosetolerance(6605f638-fae6-45ab-97c6-2f434931a1d6).html.
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