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Pajor, Ana Marie. "Transport of amino acids and glucose in brush border membrane vesicles from the gills of the marine mussel, Mytilus edulis." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184462.
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Marine mussels accumulate amino acids and glucose from seawater against considerable concentration gradients. The principal site for this uptake is the gill. Previous studies using intact, isolated gills from marine mussels have suggested that the transport mechanism involves coupling to Na⁺, similar to the mechanism of secondary active transport of amino acids and glucose in vertebrate epithelia, but until this dissertation there had been no rigorous test of this hypothesis. Brush border membrane vesicles (BBMV) were prepared from the gills of the marine mussel, Mytilus edulis, by differential and sucrose density centrifugation. The preparation procedure isolated a population of membranes enriched in brush border membrane markers. The transport of amino acids by two pathways, the alanine-lysine pathway (AK) and the alanine-proline pathway (AP), and the uptake of glucose was studied in the BBMV. The mechanism of transport through the three transport pathways is BBMV involved coupling to Na⁺. Concentrative uptake through the AK pathway, which transported alanine and lysine, also occurred in the presence of Li⁺ and K⁺ gradients. This pathway was the major route for alanine transport in BBMV. The AP pathway transported alanine and proline, and was strictly dependent on Na⁺. Glucose transport in gill BBMV resembled quite closely the Na⁺-coupled transport of glucose in vertebrate epithelia in such characteristics as Na⁺ and substrate specifically, and electrogenicity. Transport through the two amino acid uptake pathways (AK and AP) and through the glucose uptake pathway could be described by Michaelis-Menten kinetics, with high substrate affinities (K(t)'s below 10 μM). Furthermore, it is likely that multiple Na⁺ ions are involved in the transport of these amino acids and glucose in mussel gill BBMV. It appears that these transporters are adapted for function at low substrate concentrations and against large concentration gradients.
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Betley, Stephen. "Regulation of hepatocyte function by insulin, growth hormone and thyroid hormones." Thesis, University of Newcastle Upon Tyne, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287415.
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Scarano, Wellerson Rodrigo. "Repercussões histopatologicas na prostata ventral do gerbilo da Mongolia (Merinones unguiculatus) apos suplementação por hormonios esteroides." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317918.
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Orientador: Sebastião Roberto TabogaTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: O tecido prostático é susceptível aos desníveis hormonais provocados, principalmente pelo processo de envelhecimento. A hiperplasia benigna prostática e o câncer de próstata são doenças que acometem uma grande parcela da população masculina, e parecem estar envolvidas com alterações hormonais. Por isso, o esclarecimento dos processos celulares e teciduais envolvendo os hormônios sexuais: testosterona e estradiol são, sem dúvida, importantes para o entendimento da etiologia desses processos patológicos. O gerbilo (Meriones unguiculatus) foi utilizado como modelo experimental pois, segundo a literatura, é susceptível ao aparecimento de lesões autóctones e responde bem à carcinogênese experimental, mostrando-se um bom modelo experimental. Numa primeira etapa, foram utilizados animais de três idades diferentes: púbere, adulta e senil. Esses animais foram submetidos à suplementação androgênica e as próstatas ventrais foram destinadas a análises histopatológicas, quantitativas, imunocitoquímicas e ultraestruturais. Foi observado aumento no peso da glândula e também na altura das células epiteliais em todas as idades. Tal aumento reflete o aumento da capacidade sintética observada pela dilatação das organelas de síntese, às vezes de aspecto vesiculoso, ocupando toda a região supranuclear. Nos animais adultos e velhos foram notadas regiões hiperplásicas e displásicas freqüentemente associadas a Neoplasias Intraepiteliais de diferentes graus e a adenocarcinomas. Houve aumento na espessura da camada de células musculares lisas (CML) ao redor dos ácinos nos animais púberes e adultos, enquanto nos animais velhos houve diminuição dessa camada. Além disso, as CML se mostraram aparentemente hipertróficas e com maior atividade sintética nos animais púberes e adultos. Foi notado aparente aumento da vascularização periacinar, onde se observou a presença de freqüentes vasos sanguíneos em todas as idades após o tratamento. Ademais, em todas as idades foi observado aumento da densidade de marcação de receptores androgênicos após o tratamento, evidenciando a possível relação desses receptores com os efeitos observados. Em uma segunda etapa experimental, avaliou-se o efeito do estradiol sobre o tecido prostático intacto e hipoandrogênico em animais adultos, tentando com isso simular situações de descompensação hormonal, típicas da senilidade. As alterações epiteliais foram freqüentes nos animais tratados com estradiol onde se observou aumento na altura das células epiteliais, aparecimento de regiões de intensa displasia e hiperplasia, e a formação de PINs. Outro aspecto que independe da presença da testosterona é o arranjo dos elementos fibrilares e não fibrilares da matriz extracelular entre as CML, apontando para um possível papel dessas células no rearranjo e na síntese desses componentes após os tratamentos estrogênicos. Nos animais castrados observou-se acúmulo de elementos da matriz extracelular sob o epitélio e em animais intactos presença desses elementos dispersos e escassos. Em ambos os grupos: intactos e castrados, notou-se que as CML e os fibroblastos apresentam fenótipo secretor acentuado após o tratamento com estradiol. Houve aumento na densidade de marcação ERa e AR positivos em regiões de hiperplasia apontando para um possível papel desses receptores na formação de lesões pré-malígnas e malignas. Portando, conclui-se que o gerbilo é susceptível a ação da testosterona e do estradiol, os quais provocam desarranjos estruturais e ultraestruturais de cunho patológico e funcional, mostrando-se um ótimo modelo para o estudo das doenças prostáticas de etiologia hormonal
Abstract: Not informed.
Doutorado
Biologia Celular
Doutor em Biologia Celular e Estrutural
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Uchuya, Castillo Luis Joël. "Étude du signal véhiculé par les hormones thyroïdiennes dans la physiopathologie intestinale." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1221/document.
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L'épithélium intestinal est caractérisé par un renouvellement et une différenciation continus dépendant des cellules souches somatiques situées au fond des cryptes. Le renouvellement rapide est assuré par plusieurs réseaux de voies signalisation dont la dérégulation peut être à l'origine de l'initiation et/ou de la progression tumorale. Mon laboratoire d'accueil a décrit l'implication des hormones thyroïdiennes et de leur récepteur nucléaire TRa1 dans le contrôle de l'homéostasie de l'épithélium intestinal via la régulation de la voie Wnt/b-caténine d'une part et l'implication de TRa1 dans l'induction de tumeurs intestinales grâce à des souris surexprimant TRa1 d'autre part. De plus, dans un contexte APC muté, l'expression transgénique de TRa1 accélère la progression tumorale et favorise la dissémination métastatique. Des analyses transcriptomiques mettent en évidence une forte activation de la voie Wnt par TRa1. Ces résultats ont été confirmés chez l'homme en étudiant la régulation de la voie Wnt par TRa1 dans des carcinomes colorectaux (CRC). Nous avons confirmé la surexpression de TRa1 dans les tumeurs humaines et validé son impact sur la voie Wnt tant dans les tumeurs humaines que dans des lignées cellulaires et sur leur agressivité. L'ensemble des données montre une forte implication de TRa1 dans la tumorigenèse chez la souris et chez l'homme et ouvrent des portes pour des recherches visant TRa1 comme cible de traitement thérapeutique contre le cancerThe intestinal epithelium is characterized by constant renewal and differentiation due to the presence of stem cells located at the bottom of the crypts. This permanent renewal depends on the crosstalk between several signaling pathways whose alteration can lead to tumor initiation and progression. Our team demonstrated the implication of the thyroid hormones and their nuclear receptor TRa1 in the control of the intestinal epithelium homeostasis through the regulation of the Wnt pathway. Moreover, the overexpression of TRa1 in the intestinal epithelium of mice is sufficient to promote tumor initiation, and in an APC loss of function context, it accelerates tumor progression highlighting its oncogenic potential. Through gene expression profiling, we highlighted an activation of the Wnt pathway activity by TRa1 during tumor progression. We next confirm these results in human patient samples by demonstrating that high TRa1 expression in tumors invariably is associated with an increased Wnt pathway activity. In addition, in CRC cell lines, TRa1-associated WNT pathway activation enhances their aggressiveness. Altogether these results showed the implication of TRa1 in intestinal carcinogenesis and open avenues for new therapeutic treatment against TRa1 targeting TRa1
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McGinley, Susan. "Insect Hormones and Anti-Hormones: Protecting Plants and Public Health." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 1995. http://hdl.handle.net/10150/622378.
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Hussein, Mohamed Osman. "Hormonal modulation of Leydig cell membrane luteinizing hormone receptors /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487267024995937.
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Stevens, Jeffrey David. "LHRH fusion protein vaccines in beef heifers and bovine ectopic ovarian xenografting." Online access for everyone, 2004. http://www.dissertations.wsu.edu/Dissertations/Fall2004/J%5FStevens%5F092204.pdf.
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Edholm, Therese. "The role of incretin peptides and ghrelin in upper gut motility and metabolic control /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-937-8/.
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Kallmeier, Robert Charles. "Molecular studies of luteinizing hormone-releasing hormones in the brain of domestic fowl." Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306719.
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Thompson, Jennifer Jo, Cheryl Ritenbaugh, and Mark Nichter. "Why women choose compounded bioidentical hormone therapy: lessons from a qualitative study of menopausal decision-making." BIOMED CENTRAL LTD, 2017. http://hdl.handle.net/10150/626039.
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Background: In recent years, compounded bioidentical hormone therapy (CBHT) has emerged as a popular alternative to manufactured, FDA approved hormone therapy (HT)-despite concerns within the medical community and the availability of new FDA approved "bioidentical" products. This study aims to characterize the motivations for using CBHT in a U.S. sample of ordinary midlife women. Methods: We analyze data collected from 21 current and former users of CBHT who participated in a larger qualitative study of menopausal decision-making among U.S. women. Interviews and focus groups were audio-recorded, transcribed verbatim, and analyzed thematically using an iterative inductive and deductive process. Results: Although women's individual motivations varied, two overarching themes emerged: "push motivations" that drove women away from conventional HT and from alternative therapies, and "pull motivations" that attracted women to CBHT. Push motivations focused on (1) fear and uncertainty about the safety of conventional HT, (2) an aversion to conjugated estrogens in particular, and (3) and overarching distrust of a medical system perceived as dismissive of their concerns and overly reliant on pharmaceuticals. Participants also voiced dissatisfaction with the effectiveness of herbal and soy supplements. Participants were attracted to CBHT because they perceive it to be (1) effective in managing menopausal symptoms, (2) safer than conventional HT, (3) tailored to their individual bodies and needs, and (4) accompanied by enhanced clinical care and attention. Conclusions: This study finds that women draw upon a range of "push" and "pull" motivations in their decision to use CBHT. Importantly, we find that women are not only seeking alternatives to conventional pharmaceuticals, but alternatives to conventional care where their menopausal experience is solicited, their treatment goals are heard, and they are engaged as agents in managing their own menopause. The significance of this finding goes beyond understanding why women choose CBHT. Women making menopause treatment decisions of all kinds would benefit from greater shared decision-making in the clinical context in which they are explicitly invited to share their experiences, priorities, and preferences. This would also provide an opportunity for clinicians to discuss the pros and cons of conventional HT, CBHT, and other approaches to managing menopause.
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Hassan, A. Quamrul. "Molecular complementation of mutant thyroid hormone receptors that disrupt transactivation mechanism." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 9.11 Mb., 175 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3205433.
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Davies, Mina C. G. "Factors affecting embryo mortality in ewe lambs." Thesis, Aberystwyth University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340852.
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Villar, David. "Hormonal regulation of the fibre growth and moult cycle in cashmere goats." Thesis, University of Aberdeen, 1998. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU106170.
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The role of selected hormones in the control of hair follicle activity, fibre growth and moult in cashmere goats was investigated by manipulation of prolactin (PRL), thyroid hormones, and growth hormone (GH) individually or in combination. In experiment 1, the effect of different doses of the anti-thyroid drug "propylthiouracil" (PTU), on thyroxine (T4) and triiodothyronine (T3) profiles and deiodinase enzyme activities in liver, kidney and skin tissues was determined. Types II and III deiodinase enzymes were found to be present in goat skin but not type I. It was concluded that the supply of T3 within the skin was partly independent of circulating hormone profiles. In experiment 2, goats were treated with PTU, triiodothyronine (T3) and bromocriptine (Br) to decrease T3 availability to tissues and circulating PRL concentrations, respectively. Treatment with Br delayed the spring rise in plasma PRL concentrations (P=0.06) and primary (P<0.05) hair follicle activity, and delayed moult onset (P<0.01). PTU treatment did not significantly affect hair follicle activity but generally delayed the time of moult onset (P<0.05). The effects of the treatments were not additive, indicating that the actions of the two hormones were not independent. The effects of PTU and Br treatments were not exerted through changes in IGF-I binding activity in the skin, but binding was greater (P<0.01) in April than November. In experiment 3, treatment with bovine somatotropin (bST), T4 or metoclopramide to increase circulating concentrations of GH, T4 or PRL, failed to prolong the period of anagen in hair follicles, but bST increased fibre growth rate (P<0.05) and this was associated with higher circulating IGF-I concentrations. It is concluded that manipulation of the cycle of the cashmere-producing hair follicle is unlikely to be achieved through manipulation of circulating hormone concentrations alone and that much regulation of hair follicle activity occurs within the skin itself, possibly through changes in enzymes that control the supply of T3 to the follicles, in hormone receptor activity, and in the rate of synthesis of IGF-I and other growth factors within the skin.
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Zheng, Jianfei. "Development of thyroid hormone receptor-targeting conjugates." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 130 p, 2009. http://proquest.umi.com/pqdweb?did=1833641661&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Kask, Kristiina. "Hormones, Mood and Cognition." Doctoral thesis, Uppsala universitet, Institutionen för kvinnors och barns hälsa, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9365.
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Ovarian steroid hormones are neuroactive steroids with widespread actions in the brain, and are thus able to influence mood, behavior and cognition. In this thesis the effects of progesterone withdrawal and the direct effects of the progesterone metabolite allopregnanolone are evaluated. Allopregnanolone, through binding to the GABAA receptor complex, enhances inhibitory neurotransmission, thus exerting anxiolytic, sedative and antiepileptic effects. The acoustic startle response (ASR) is a withdrawal reflex evoked by sudden or noxious auditory stimuli, and can be measured in humans as an eye blink. ASR is significantly increased in several anxiety disorders, and notably also during progesterone withdrawal. Sensorimotor gating can be assessed by measuring prepulse inhibition of the startle response (PPI). The CNS circuits regulating PPI are sensitive to hormone fluctuations. GABAergic drugs are involved in cognitive impairment and animal studies have indicated that allopregnanolone may inhibit learning. The main purpose of this research was to evaluate the behavioral effects of progesterone withdrawal on the startle response and sensorimotor gating in PMDD patients and healthy controls, in healthy third trimester pregnant women and healthy postpartum women. A second aim was to evaluate allopregnanolone effects on memory and cognition in healthy women and also on the startle response and PPI. We found that PMDD patients have an increased startle response across the menstrual cycle and a deficiency in sensorimotor gating during the late luteal phase. Ovarian steroids affect sensorimotor gating; pregnant women have lower levels of PPI than late postpartum women. Acutely administered allopregnanolone did not affect the ASR or PPI. Allopregnanolone impairs episodic memory in healthy women. In conclusion, our studies suggest that ovarian steroids, including allopregnanolone, do not influence the startle response. Ovarian steroids affect sensorimotor gating; pregnancy, a condition with high levels of ovarian steroids, suppresses PPI. Theoretically, the variability in PPI across reproductive events is due to effects mediated by the progesterone or estradiol receptors but is not mediated by allopregnanolone. PMDD patients display decreased PPI during the late luteal phase, suggesting underlying pathophysiology in common with other anxiety disorders. The most vulnerable memory system, the episodic memory, is impaired by the allopregnanolone in healthy women.
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Le, Roux Carel Wynand. "Gut hormones and appetite." Thesis, Imperial College London, 2005. http://hdl.handle.net/10044/1/7840.
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ARNIAUD, DENIS. "Rhumatismes inflammatoires et hormones." Aix-Marseille 2, 1994. http://www.theses.fr/1994AIX20867.
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Baynham, Mark Kevin. "Gibberellin plant growth hormones." Thesis, University of Sussex, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328329.
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Donald, Angela Sheila. "Sex hormones in dermatophytes." Thesis, University of Aberdeen, 1990. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU078356.
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1. Culture media and conditions were developed to maximize the sexual development of Nannizzia incurvata using liquid culture and solid media, modified Sabouraud's 1/6 salts + hair medium being the most suitable. 2. Strong evidence for the existence of two sex hormones which regulate sexual differentiation was found. It is proposed that these hormones are named (+)-factor (which is produced by (+)-cells and induce a sexual response in (-)-cells) and (-)-factor (which is produced by (-)-cells and induce a sexual response in (+)-cells). 3. Addition of active extracts of concentrated mated culture filtrates caused a switch from asexual to sexual development and the formation of the characteristic sexual cleistothecia. The hormones present are probably extracellular, as mycelial extracts do not cause this response. 4. Further evidence for the existence of these sex hormones was achieved by separation of compatible strains by a semi-permeable membrane, cellophane, which allowed diffusion of the hormones through the medium yet prevented physical, hyphal interactions between the two strains. Sexual morphogenesis occurred in both strains. 5. Both (+)-factor and (-)-factor were shown to be non-volatile by further experiments separating colonies with cellophane membranes. 6. (-)-Factor was solvent extractable using diethyl ether or ethyl acetate, while (+)-factor remained in the aqueous phase. Thus, (-)-factor is more hydrophobic yet less polar and (+)-factor is more hydrophilic yet more polar.
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Rodway, Marie R. "Effector mechanisms in the endocrine control of steroidogenesis." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/31411.
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Production of hormones in the ovary is controlled by endocrine, paracrine, autocrine and intracrine influences. Similar controls may exist in the placenta. I wished to investigate the involvement of second messengers in the action of hormones in control of hormonogenesis in rat ovary and human placenta. The second messengers involved in the action of gonadotropin-releasing hormone (GnRH) and prostaglandin (PG) F₂[formula omitted] were investigated in rat granulosa and luteal cells. As well, the endocrine role of GnRH in the placenta and the possible second messengers involved were investigated.
Monolayer cultures of rat granulosa and luteal cells and human placental cells were prepared. Rat granulosa cells were mechanically dispersed; rat luteal cells were enzymatically dispersed with collagenase and DNase. Rat granulosa cells were treated during the first 24 hours in culture; rat luteal cells were treated up to 3 days after dispersion. Radioimmunoassay of medium was used to determine the effect of treatments on hormone production. Studies which examined the effect of hormones on the intracellular free calcium concentration ([Ca²⁺]i) in single cells using the calcium sensitive fluorescent dye, Fura-2, were done in monolayer rat granulosa and luteal cell cultures. Human placental cells, from first trimester and term placentae, were dispersed using trypsin-DNase or collagenase-DNase. Cells were cultured for 2 days prior to treatment. The effects of treatments on production of steroid (progesterone and estrogen),
glycoprotein (human chorionic gonadotropin; hCG) and protein (human placental lactogen; hPL) hormones were determined by radioimmunoassay of the medium.
In rat granulosa and luteal cell cultures, I examined the effect of a number of hormones and second messengers. Effects of follicle-stimulating hormone (FSH), luteinizing hormone (LH), cyclic adenosine monophosphate (cAMP), GnRH and PGF₂[formula omitted] on ovarian hormonogenesis have been previously reported. Changes in cytosolic free calcium concentrations ([Ca²⁺]i) in response to PGF₂[formula omitted] were measured in single rat granulosa and luteal cells. I found that in 34% of granulosa cells, and 53% of luteal cells, there was a 3 to 4 fold increase in resting [Ca²⁺]i within 30 seconds of administration of PGF₂[formula omitted]. Many cells which responded to PGF₂[formula omitted] also responded to GnRH (39% of granulosa cells; 67% of luteal cells). The immediate source of the increased [Ca²⁺]i appeared to be common intracellular stores.
No change in hormone production in response to GnRH in placental cell cultures was seen. Trypsin dispersion may have damaged cell surface receptors, therefore the effect of second messengers on hormone production in these cultures was examined. In term and first trimester trophoblast cultures, I observed the following effects with 8-bromo-cyclic adenosine monophosphate (8-br-cAMP): inhibited estrogen production from the supplied androgen precursors; stimulated hCG production; stimulated hPL production in first trimester placental cell cultures (hPL was not measured in enough term cultures to determine the effect of 8-br-cAMP), and stimulated progesterone production. I also
investigated the effects of activators and inhibitors of the phosphoinositide (PtdIns(4,5)P₂) breakdown second messenger pathway (TPA, A23187, arachidonic acid); no effects of these agents were seen. Other hormones suspected of having endocrine, paracrine or autocrine effects in the placenta were tested without effect.
I conclude that GnRH and PGF₂[formula omitted] cause increases in [Ca²]i in rat ovarian cells, from common intracellular stores of calcium, and that the production of hormones by the human placenta may be under regulation of an agent or agents which induce production of cAMP.Medicine, Faculty of
Obstetrics and Gynaecology, Department of
Graduate
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Levin, Tracy M. "Evidence for the existence of juvenile hormone in the horseshoe crab." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0528103-140647.
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Gross, Bernadette. "Structure du gène humain du récepteur de la TSH : polarisation des récepteurs de la LH dans les cellules MDCK." Paris 11, 1993. http://www.theses.fr/1993PA11T016.
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Brischoux, Frédéric. "Etude ontogénétique du système à hormone de mélano-concentration (MCH) chez le rat et régionalisation de l'hypothalamus." Besançon, 2002. http://www.theses.fr/2002BESA0006.
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Marion, Sébastien. "Influence de la dynamique intracellulaire des kinases spécifiques des récepteurs couplés aux protéines G (GRKs) et des β-arrestines sur l'état d'activation du récepteur de l'hormone folliculo-stimulante (RFSH)." Tours, 2002. http://www.theses.fr/2002TOUR4001.
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Le récepteur de l'hormone folliculo-stimulante (RFSH), exprimé chez le mâle par les cellules de Sertoli, est un récepteur couplé aux protéines G (GPCR). En présence de son agoniste, il perd rapidement sa capacité à activer son effecteur principal, l'adénylate cyclase. Les travaux menés sur des lignées cellulaires transfectées par le RFSH, ont montré que cette désensibilisation requiert la phosphorylation du récepteur occupé par son agoniste par les kinases spécifiques des GPCRs, les GRKs. Cette phosphorylation provoque la liaison des bêta-arrestines (β-arr) au RFSH, son découplage avec la protéine G alphas et l'internalisation clathrine-dépendante du complexe récepteur-ligand. Nous avons mis en évidence que le RFSH interagit de façon agoniste-dépendante avec des GRKs déficientes pour leur activité kinase impliquant que le découplage du RFSH pourrait résulter d'un encombrement stérique plutôt que d'une phosphorylation. Nous avons établi que la surexpression de chacune des GRKs 2, 3, 5 et 6 et β-arr1 et 2 découple la réponse FSH en terme de production d'AMPc dans des cellules de Sertoli en culture primaire. De plus, la GRK2 et la β-arr1 endogènes sont recrutées sous stimulation vers les membranes, confirmant l'implication des GRKs et β-arr endogènes dans la modulation de la réponse FSH dans les cellules de Sertoli. Afin de préciser la cinétique des événements nous avons suivi le trafic intracellulaire in situ du RFSH, des GRKs et β-arr. Le RFSH surexprimé en cellules Cos7 est membranaire et la GRK2 et la β-arr1 sont cytosoliques. Après 4 min. De stimulation FSH, le récepteur colocalise avec la GRK2 et la β-arr1. Après 30 à 60 min. De stimulation le RFSH, la GRK2 et la β-arr1 sont concentrés dans un compartiment péri-nucléaire, avant que le RFSH ne recycle vers la membrane selon un cycle long, alors que la GRK2 et la β-arr1 retrouvent une distribution cytosolique. Aucune colocalisation du RFSH avec la β-arr2 n'a été observée dans la cinétique de stimulation étudiée.
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Billon, Cyrielle. "Hormones thyroïdiennes et désordres métaboliques." Thesis, Lyon, École normale supérieure, 2012. http://www.theses.fr/2012ENSL0720.
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Les hormones thyroïdiennes jouent un rôle dans de nombreux processus métabolique tels que le développement, la croissance et le contrôle du métabolisme. Les HT se fixent sur leurs récepteurs nucléaires, les TR (TRalpha et beta). Ces TR sont des facteurs de transcription dont l’activité est contrôlée par la fixation de leur ligand, ils appartiennent à la super famille des récepteurs nucléaires d’hormone. Au cours de ma thèse je me suis intéressée aux rôles des TR dans deux contextes particuliers. Dans un premier temps, j’ai pu mettre en évidence le rôle de TRbeta dans la régulation du métabolisme hépatique via l’activation d’un gène clé ChREBP permettant la détection du glucose. Par l’utilisation d’animaux transgéniques et des systèmes in vitro, j’ai pu montrer que TRbeta régule positivement l’expression de ChREBP via le fixation sur son élément de réponse présent de le promoteur. Nous avons pu montrer que cette activation est isoforme spécifique, indépendante d’un autre récepteur nucléaire LXR. Dans un deuxième temps, j’ai montré que l’autre isoforme de TR, TRalpha est impliqué dans le développement de l’athérosclérose, une maladie cardiovasculaire. Par l’utilisation d’un modèle de souris transgénique, j’ai pu mettre en évidence que TRalpha possède à la fois un rôle anti-inflammatoire et également il est capable de stimuler l’élimination du cholestérol par les macrophages. L’absence de ce récepteur induit une augmentation du développement de la maladie ainsi que des cytokines circulantes chez la souris. Par l’utilisation d’un système in vitro, j’ai pu mettre en évidence que l’absence de TRalpha diminue l’efflux de cholestérol dans les macrophages de souris. Ces données suggèrent un nouveau rôle des HT/TR dans le développement de pathologies humaines, notamment un effet anti-inflammatoire longtemps supposer mais mis en évidence que très récemmentThyroid hormones (TH) play a role in many processes such as development, growth and metabolic control. HT bind to their nuclear receptors, the TR (TRalpha and beta). TRs belong to the superfamily of nuclear hormone receptors. These TRs are transcription factors whose activity is controlled by the binding of their ligand. During my PhD thesis I focused on the roles of TR in two contexts. Initially, I highlighted the role of TRbeta in the regulation of the hepatic metabolism via the activation of the key gene ChREBP, a glucose-responsive transcription factor. Using transgenic animal models and in vitro systems, I showed that TRbeta up regulates the expression of ChREBP via binding to its response element present in the promoter. I have shown that this activation is isoform specific and independent of another nuclear receptor LXR. In a second part, I demonstrated that the TRalpha isoform is involved in the development of atherosclerosis, a cardiovascular disease. Using a transgenic mice model, I observed that TRalpha has an anti-inflammatory effect and it is also able to stimulate the reverse cholesterol transport by macrophages. The absence of this receptor induces an increase in the development of the disease as well as in the level of circulating cytokines in mice. The deletion of TRalpha decreases the cholesterol efflux in bone marrow derived macrophages in vitro and it is correlated with a decrease of ABCA1 expression. All these data suggest a novel role of HT / TR in the development of human pathologies, including an anti-inflammatory role assumed, but recently demonstrated
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Diekman, Mattheus Jozef Maria. "Thyroid hormones, lipids and endothelium." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2000. http://dare.uva.nl/document/84351.
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Smith, Kirsty Louise. "Metabolic hormones and energy homeostasis." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411789.
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Watts, Julian Daniel. "Thymic hormones : structure and function." Thesis, University of Portsmouth, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328160.
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Cleator, M. "Developmental hormones in parasitic nematodes." Thesis, University of Liverpool, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356250.
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O'Hanlon, Graham Michael. "Developmental hormones in ascarid nematodes." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293137.
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Foster, Jeremy Michael. "Hormones and isoprenoids in trematodes." Thesis, University of Liverpool, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303679.
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Gooding, Kim Mary. "Sex hormones and the microcirculation." Thesis, University of Exeter, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248164.
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Oh, Hannah. "Lifestyle, Hormones, and Breast Cancer." Thesis, Harvard University, 2014. http://nrs.harvard.edu/urn-3:HUL.InstRepos:14117761.
Full textAbstract:
Breast cancer is a leading cause of cancer and the second leading cause of cancer death among women in the US. Although many risk factors for breast cancer are known, few are modifiable and little is known about ways to prevent its incidence.
Early-life body size is inversely associated with both premenopausal and postmenopausal breast cancer risk, suggesting an excess risk in lean girls. In a prospective analysis within the Nurses’ Health Study (NHS) II, Chapter 1 examines whether adolescent physical activity mitigates the excess risk of breast cancer associated with early-life body leanness. Lean girls were at higher risk of breast cancer, regardless of the level of adolescent physical activity; however, the association was slightly, though not significantly, attenuated among the most active girls.
Breast cancer is hormone-related cancer; estrogen metabolites (EM) are both estrogenic and genotoxic, suggesting factors that alter the pattern of estrogen metabolism may contribute to breast carcinogenesis. With the application of advanced technology that measures 15 different individual estrogens and EM in urine, Chapter 2 examines the associations of dietary fiber and macronutrients intake with detailed estrogen metabolism in a cross-sectional analysis within the NHSII. Few significant associations were identified: a positive association between total fiber intake and 4-methoxyestradiol, an inverse association between total fiber intake and 17-epiestriol, and inverse associations for polyunsaturated and trans-fat intakes with 17-epiestriol.
The tissue-specific responsiveness to potentially carcinogenic hormones, estrogen and progesterone, is partially regulated by the tissue expression of receptors that bind these hormones. Using benign breast biopsy samples collected in a nested case-control study within the NHS and NHSII, Chapter 3 assesses estrogen receptor (ER), progesterone receptor (PR), and proliferative marker Ki67 expression in normal breast tissue in relation to subsequent breast cancer risk. In this case-control analysis, PR expression in normal breast tissue was significantly positively associated with breast cancer risk in premenopausal women. ER and Ki67 expression was not significantly associated with breast cancer risk; however, our power was limited.
Results of this dissertation help elucidate the underlying biologic mechanisms of breast cancer and enhance our understanding of the link between risk factors and breast cancer risk.
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Neary, Nicola Marguerite. "Gut hormones and energy homeostasis." Thesis, Imperial College London, 2007. http://hdl.handle.net/10044/1/7152.
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Von, Boetticher S. "Investigating the mechanism of transcriptional regulation of the gonadotropin-releasing hormone receptor (GnRHR) gene by dexamethasone." Thesis, Link to the online version, 2008. http://hdl.handle.net/10019/1796.
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Barsnick, Rosa. "Hormones of Energy Metabolism in Critically Ill Foals: Insulin, Glucagon, Leptin, Adiponectin, Ghrelin and Growth Hormone." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275523617.
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Wormald, Patricia J. "GnRH and neuropeptide regulation of gonadotropin secretion from cultured human pituitary cells." Doctoral thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/27168.
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Gonadotropin-releasing hormone (GnRH) and its superactive analogues are currently being used in the treatment of a number of endocrine disorders, such as endometriosis, precocious puberty, infertility and prostatic cancer. Selection of these analogues for clinical use have been previously based on their activities in animal models. This thesis has therefore investigated the binding characteristics of the human GnRH receptor, in comparison to those of the rat receptor, as well as the activities of a number of GnRH analogues for stimulating luteinising hormone (LH) and follicle stimulating hormone (FSH) secretion from cultured human pituitary cells. The establishment of a human pituitary bioassay system has further made possible the investigation of the direct regulatory roles of GnRH and other neuropeptides in man. To date, such studies in man have been performed in vivo and are thus complicated by the simultaneous interactions of numerous modulators.
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Damasceno, Danielle Zanerato. "Indução a espermiação do mandi-pintado, Pimelodus britskii no período reprodutivo (Teleostei: Pimelodidae) /." Jaboticabal, 2014. http://hdl.handle.net/11449/108928.
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Orientador: Elizabeth RomagosaBanca: Sérgio Ricardo Batlouni
Banca: Alexandre Ninhaus Silveira
Resumo: O objetivo deste trabalho foi caracterizar o sêmen de Pimelodus britskii através de diferentes métodos de coleta e doses hormonais. O experimento foi executado em dois períodos reprodutivos, novembro/2011 a março/2012 e outubro/2012 a março/2013. No primeiro período reprodutivo (Experimento 1) em todos os meses 12 peixes foram divididos em dois grupos, um grupo induzido com Extrato Hipofisádo de Carpa-EHC (3,0 mg.kg-1) e um grupo sem indução hormonal, após 240 unidades térmicas acumuladas-UTAs os peixes dos dois grupos foram eutanasiados e tiveram seus testículos macerados. No segundo período reprodutivo (Experimento 2) 30 peixes foram divididos em cinco grupos para comparação de diferentes doses de EHC e Gonadotrofina Coriônica humana-hCG na espermiação (T1: controle; T2: 3,0 mg.kg-1EHC; T3: 0,5 mg.kg-1+3,0 mg.kg-1EHC; T4: 0,5mg.kg-1+7,0 mg.kg-1EHC; T5: 200UI.kg-1hCG), sendo que neste período os mesmos peixes foram utilizados todos os meses, e após 240 UTAs o sêmen foi coletado através de massagem abdominal. Foram avaliadas a motilidade e velocidade espermática por meio do software CASA (Computer Assisted Sperm Analysis). As variáveis seminais por meio do Statistica 7.0. Por meio da maceração, verificou-se alterações na cor (branco a amarelado), pH (6 a 7) e concentração espermática (11,9x109±4,16x109 a 9,15x109±3,55x109 espermatozoides/mL-1). O volume mostrou relação entre meses e tratamentos (p<0,05). Para todos os exemplares a motilidade foi superior em nov/2011, diminuindo gradativamente até fev/2012. O mesmo ocorreu em relação aos valores dos IGS (p<0,05), mostrando a ação da indução hormonal no volume seminal. Os peixes do Experimento1 liberaram volume reduzido de sêmen ...
Abstract: The aim of this study was to characterize the semen Pimelodus britskii through different collection methods and hormonal doses. The experiment was run in two reproductive periods, November/2011 to March/2012 and October/2012 to March/2013. In the first breeding season (Experiment 1 ) in all months 12 fish were divided into two groups, one experimental group with Carp Pituitary Extract - EHC (3.0 mg.kg- 1) and a group without hormonal induction, after 240 units accumulated thermal-UTA fish from both groups were euthanized and had their macerated testes. In the second reproductive period (Experiment 2 ) 30 fish were divided into five groups for comparison of different doses of human Chorionic Gonadotropin-hCG and EHC in spermiation (T1: Control, T2: 3,0mg.kg-1 EHC, T3: 0,5 mg.kg-1 +3,0 mg.kg-1 EHC , T4: 0,5 mg.kg-1 +7,0 mg.kg-1 EHC , T5: 200UI.kg-1 hCG ) , and in this period the same fish were used every month, and after 240 UTA semen was collected by abdominal massage. Motility and sperm velocity were evaluated through the CASA software (Computer Assisted Sperm Analysis). The seminal variables using Statistica 7.0. Through the soaking, there was color change (white to yellow), pH (6 to 7) and sperm concentration (11,9x109±4,16x109 to 9,15x109±3,55x109 spermatozoa/mL-1). The volum months showed relationship between treatments (p<0,05). For all copies motility was higher in November/2011, decreasing gradually until February/2012. The same occurred with the values of the IGS (p<0,05), showing the action of hormonal induction in seminal volume ...
Mestre
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Baillot, Aurélie. "Réentraînement à l'effort chez des sujets atteints du syndrome métabolique : impact sur les réponses hormonales et la qualité de vie." Thesis, Orléans, 2010. http://www.theses.fr/2010ORLE2038/document.
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Le syndrome métabolique (Smet) désigne une combinaison d'anomalies métaboliques (obésité, insulinorésistance, dyslipidémie et hypertension) reliées entre elles, dont l‘origine n‘est pas encore définie. D‘après la littérature, les personnes atteintes du Smet présentent des altérations hormonales et de la qualité de vie, mais ce concept étant relativement récent, peu d‘études se sont intéressées aux effets de l‘activité physique régulière sur ces paramètres. Notre travail se divise en deux parties. Dans un premier temps, nous avons étudié la corrélation entre les concentrations hormonales surrénaliennes plasmatiques et salivaires au repos et à l‘exercice chez les hommes atteints du Smet. Il apparait que la corrélation obtenue au repos n‘est pas altérée de manière significative à l‘exercice. Dans un second temps, nous avons étudié les effets d‘une activité physique régulière contrôlée de 8 semaines sur les réponses hypophysaires, surrénaliennes et androgéniques, ainsi que sur les capacités physiques et la qualité de vie chez des hommes atteints du Smet. Nos résultats montrent qu‘un entraînement aérobie de courte durée ne provoque pas de changement anthropométrique mais induit une diminution significative du cortisol salivaire au repos sans modifier les autres concentrations hormonales. Par ailleurs, les capacités physiques et la dimension psycho-sociale de la qualité de vie sont significativement améliorées. Ces données confirment l‘effet bénéfique de l‘activité physique régulière sur les capacités physiques et la qualité de vie, tout en laissant supposer que le cortisol salivaire serait un marqueur précoce signant l‘amélioration des capacités physiques chez les sujets atteints du Smet. D‘autres études, incluant des cohortes plus larges et des durées de réentraînement à l‘effort plus importantes, seraient nécessaires pour compléter ce travailThe metabolic syndrome (Mets) is a cluster of metabolically related abnormalities (abdominal obesity insulin resistance, dyslipidemia and hypertension), with no obvious defined cause. In the literature, individuals with Mets seem to have hormonal and quality of life alterations, but this concept is relatively recent and few studies have investigated the effects of regular physical activity on these parameters. Our work divides into two parts. First, we studied the correlation between plasmatic and saliva adrenocortical hormonal at rest and during exercise in men with Mets. It appears that the correlation obtained at rest is maintained during exercise. Secondly, we studied the effects of 8 weeks of controlled regular physical activity on the pituitary, adrenocortical and androgenic hormones, physical capacity and quality of life in men with Mets. Our results show that aerobic exercise training does not induce anthropometric modifications but decreases significantly basal saliva cortisol without any other hormonal change. In parallel, physical capacity and psychosocial impact dimension of quality of life are significantly improved. These data confirm the beneficial effect of regular physical activity on physical capacity and quality of life. It is tempting to suggest that saliva cortisol could be an early marker reflecting improvement of physical capacities in individuals with Mets. Further works with larger cohort and longer training programs are required to complete this work
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Wihlbäck, Anna-Carin. "Ovarian hormones and effects in the brain : studies of neurosteroid sensitivity, serotonin transporter and serotonin2A receptor binding in reproductive and postmenopausal women." Umeå : Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-365.
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Wang, Ying. "Molecular and functional characterization of the prolactin receptor, prolactin-releasing peptide receptor, and growth hormone-releasing hormone receptor genes in chicken." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39556864.
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Roberts, April M. "Steroid hormone treatments alter growth characteristics in transformed human ovarian cell lines." Virtual Press, 2003. http://liblink.bsu.edu/uhtbin/catkey/1265095.
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Powell, R. C. "Evolution of the structure and function of vertebrate brain gonadotropin-releasing hormone." Master's thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/27201.
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In this study, the structure and function of gonadotropin-releasing hormone (GnRH) in different vertebrate species, in the classes Aves, Reptilia and Pisces was investigated. Acetic acid extracts were subjected to gel filtration chromatography and semipreparative high performance liquid chromatography (HPLC) to partially purify the GnRHs. The GnRH immunoreactivity was then characterized by analytical HPLC, and by assaying HPLC fractions by radioimmunoassay with region-specific antisera generated against mammalian GnRH, Gln⁸-GnRH and Trp⁷,Leu⁸-GnRH and assessing luteinizing hormone (LH)-releasing activity of fractions in a chicken dispersed anterior pituitary cell bioassay. Five GnRH molecular forms have thusfar been structurally characterized in vertebrate brain. In mammals a GnRH with the structure pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH₂ has been demonstrated in the hypothalamus (Matsuo et al., 1971; Burgus et al., 1972). Gln⁸-GnRH and His⁵,Trp⁷,Tyr⁸-GnRH were present in chicken hypothalamus (King and Millar, 1982a, 1982c; Miyamoto et al., 1983, 1984), Trp⁷,Leu⁸-GnRH in salmon brain (Sherwood et al., 1983) and Tyr³,Leu⁵,Glu⁶,Trp⁷,Lys⁸-GnRH in lamprey brain (Sherwood et al., 1986). In ostrich (Struthio camelus) hypothalamus two GnRHs with identical properties to Gln⁸-GnRH and His⁵,Trp⁷,Tyr⁸-GnRH have been demonstrated, as well as four other LR-releasing factors with different chromatographic and immunological properties to any of the known naturally-occurring GnRHs. Since Gln⁸-GnRH and His⁵,Trp⁷,Tyr⁸-GnRH were also present in chicken hypothalamus it appears likely that these two GnRHs occur in all birds. In alligator (Alligator mississippiensis) brain only two GnRHs were detected. These forms co-eluted with Gln⁸-GnRH and His⁵,Trp⁷,Tyr⁸-GnRH in two HPLC systems. They cross-reacted similarly to the two synthetic peptides with antisera directed against mammalian GnRH and Gln⁸-GnRH and released LH from chicken dispersed anterior pituitary cells in a similar manner to the synthetic peptides. The Archosaurs (alligators and crocodiles) are believed to be closely related to birds and therefore it seems likely that they should have identical GnRHs. In skink (Calcides ocellatus tiligugu) brain one GnRH, which co-eluted with His⁵,Trp⁷,Tyr⁸-GnRH, was demonstrated. Two other lizards (Cordylis nigra and Pordarcis s. sicula) have been studied (Powell et al., 1985; R.C. Powell, G. Ciarcia, V. Lance, R.P. Millar and J.A. King, submitted). In c. nigra four immunoreactive GnRHs were detected, two of which co-eluted released chicken LH similarly to, Trp⁷,Leu⁸-GnRH and with, and His⁵,Trp⁷,Tyr⁸-GnRH. In P. s. sicula a GnRH molecular form similar to Trp⁷,Leu⁸-GnRH occurred as well as two novel GnRHs. It thus appears that Gln⁸-GnRH does not occur in lower reptiles, but His⁵,Trp⁷,Tyr⁸-GnRH and/or Trp⁷,Leu⁸-GnRH do. His⁵,Trp⁷,Tyr⁸-GnRH appears to he a widespread GnRH, occurring in vertebrates as diverse as birds and elasmobranch fish. In dogfish (Poroderma africanum) brain seven factors, which stimulated release of LH from chicken dispersed anterior pituitary cells, were separated on analytical HPLC. Two of these factors were partially characterized as Trp⁷,Leu⁸-GnRH and His⁵,Trp⁷,Tyr⁸-GnRH. Three of the other forms cross-reacted with GnRH antisera, but appear to be novel GnRHs. In teleost (Coris julis) brain two GnRHs similar to Trp⁷,Leu⁸-GnRH and His⁵,Trp⁷,Tyr⁸-GnRH were present. These two GnRHs therefore appear to occur in both fish species studied. Trp⁷,Leu⁸-GnRH is widespread amongst teleost fish (Jackson and Pan, 1983; Sherwood et al., 1983; Breton et al., 1984; Sherwood et al., 1984; King and Millar, 1985). From these data it seems evident that the mammalian GnRH molecular form occurs only in mammals and amphibians, Gln⁸-GnRH in birds and higher reptiles, and Trp⁷,Leu⁸-GnRH in gnathostomes. His⁵,Trp⁷, Tyr⁸-GnRH appears to he present in numerous different vertebrates. Tyr³,Leu⁵,Glu⁶,Trp⁷,Lys⁸-GnRH has thus far only been detected in lamprey brain. A number of novel GnRHs, whose structures have not been elucidated are present.
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Van, Koesveld Marika J. "Potential applications of growth hormone-releasing peptide-6 as a growth promotant." Thesis, The University of Sydney, 2003. https://hdl.handle.net/2123/28158.
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Consumer demand for high quality, lean meat has driven pork producers to seek
new methods to maximise lean meat production and minimise fat deposition.
Manipulation of the somatotropic axis of an animal has been identified as an
effective method to increase growth efficiency and decrease adipose tissue
deposition. The potential of H-His-D-Trp-Ala-Trp-D-Phe—Lys-NHZ (GHRP-6) to
improve grth was evaluated by two methods, as a neonatal imprinting agent,
and as an orally active in—feed additive via conjugation to vitamin B12. Neonatal
imprinting with once-daily injections of GHRP-6 to piglets for three days
postnatally resulted in an 8% increase in slaughter weight when animals were fed a high protein specification diet, compared to control animals fed a standard commercial diet. The increase in growth rate appears to be due to stimulation of feed intake, although the exact mechanism causing this effect is unknown at this stage. Feed efficiency and carcass composition did not differ from control animals. Further refinement of this technology may make it a highly desirable and cost-effective method to enhance growth rate and allow animals to attain a marketable liveweight in a shorter period of time.
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Fradinger, Erica Aileen. "Isolation and developmental expression of growth hormone-releasing hormone (GRF), pituitary adenylate cyclase-activating polypeptide (PACAP) and their receptors in the zebrafish, Danio rerio." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ62513.pdf.
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Eriksson, Maria. "Adipocyte-derived hormones and cardiovascular disease." Doctoral thesis, Umeå universitet, Institutionen för folkhälsa och klinisk medicin, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-36679.
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Obesity is increasing globally and related to major changes in lifestyle. This increase is associated with an increased risk of cardiovascular disease (CVD). Knowledge about adipose tissue as a metabolic-endocrine organ has increased during the last few decades. Adipose tissue produces a number of proteins with increased body weight, many of which are important for food intake and satiety, insulin sensitivity, and vessel integrity, and aberrations have been related to atherosclerosis. Notably, the risk for developing CVD over the course of a lifetime differs between men and women. In Northern Sweden, men have a higher risk for myocardial infarction (MI). However, the incidence is declining in men but not in women. These sex differences could be due to functional and anatomical differences in the fat mass and its functions. The primary aim of this thesis was to evaluate associations between the adipocyte-derived hormones leptin and adiponectin, and fibrinolysis and other variables associated with the metabolic syndrome, and particularly whether these associations differ between men and women. Another aim was to evaluate these associations during physical exercise and pharmacological intervention (i.e. enalapril). Finally, whether leptin and adiponectin predict a first MI or sudden cardiac death with putative sex differences was also investigated. The first study used a cross-sectional design and included 72 men and women recruited from the WHO MONICA project. We found pronounced sex differences in the associations with fibrinolytic variables. Leptin was associated with fibrinolytic factors in men, whereas insulin resistance was strongly associated with all fibrinolytic factors in women. The second study was an experimental observational study with 20 men exposed to strenuous physical exercise. During exercise, leptin levels decreased and adiponectin levels increased, and both were strongly associated with an improved fibrinolytic capacity measured as decreased PAI-1 activity. Changes in insulin sensitivity were not associated with changing adiponectin levels. The third study was a randomised, double-blind, single centre clinical trial including 46 men and 37 women who had an earlier MI. The study duration was one year, and participating subjects were randomised to either placebo or ACE inhibitor (i.e. enalapril). Circulating leptin levels were not associated with enalapril treatment. During the one-year study, changes in leptin levels were associated with changes in circulating levels of tPA mass, PAI-1 mass, and tPA-PAI complex in men, but not vWF. These associations were found in all men and men on placebo treatment. In women on enalapril treatment there was an association between changes in leptin and changes in vWF. In the fourth study, the impact of leptin, adiponectin, and their ratio on future MI risk or sudden cardiac death was tested in a prospective nested casecontrol study within the framework of the WHO MONICA, Västerbotten Intervention Project (VIP), and Västerbotten Mammary Screening Program (MSP). A total 564 cases (first-ever MI or sudden cardiac death) and 1082 matched controls were selected. High leptin, low adiponectin, and a high leptin/adiponectin ratio independently predicted a first-ever MI, possibly with higher risk in men in regards to leptin. The association was found for non-fatal cases with ST-elevation MI. Subjects with low adiponectin levels had their MI earlier than those with high levels. In conclusion, the adipocyte-derived hormones leptin and adiponectin are related to the development of CVD with a sex difference, and fibrinolytic mechanisms could be possible contributors to CVD risk.
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Daja, Mirella Maria. "Enzyme activities associated with gonadotropic hormones." Thesis, University of Auckland, 1993. http://hdl.handle.net/2292/2311.
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A structural relationship between gonadotropic hormones and certain types of enzymes has been suggested in previous studies and an investigation into the possibility of enzymatic activity associated with the gonadotropic hormones has been the primary focus of the research presented in this thesis. Partial sequence homology between human chorionic gonadotropin (hCG) and α-chymotrypsin prompted the recent proposal of a tertiary structure of hCG using α-chymotrypsin as a folding template, which suggested the possibility of intrinsic peptidase activity associated with hCG. Highly purified hCG (CR127) was assayed for enzymatic activity against a range of synthetic peptide substrates and was found to exhibit Arg-specific peptidase activity. This activity was almost completely inhibited by diisopropylfluorophosphate (DFP), soybean trypsin inhibitor (STI), N-tosyl-L-phenylalanine chloromethyl ketone (TPCK) and to a lesser extent by N-α-p-tosyl-L-lysine chloromethyl ketone (TLCK), which indicated that the observed protease activity was serine protease-like. To establish whether this activity was intrinsic to the hormone or due to contaminants, extensive purification procedures were carried out. Hydrophobic interaction chromatography (HIC) and soybean trypsin inhibitor-affinity chromatography were found to effectively separate the protease activity from the hormone, indicating the presence of exogenous protease contaminants in the highly purified preparation of hCG. Further analysis by [3H]-DFP labelling of hCG and SDS-PAGE of the isolated contaminants revealed the presence of possible serine proteases with apparent molecular masses of 60 and 20 kD. Because serine proteases are known to stimulate cAMP production in the same target cells, it was necessary to determine the effects of the contaminating proteases on the receptor binding of hCG and cAMP production. The presence of these contaminants was found to have no apparent effect on the receptor binding capability of hCG, however the in vitro biological activity of hCG as determined by maximal cAMP production was decreased after HIC-HPLC purification of the hormone. These observations suggested that the serine protease-like contaminants contributed to the total cAMP production, thereby introducing significant error in biological assays that use hCG (CR127). The possible intrinsic enzymatic activity of hCG against its receptor as a natural substrate was further investigated. A membrane-bound receptor preparation was isolated from porcine ovaries and a receptor binding assay successfully established. The effects of hCG binding upon the membrane-bound receptor were studied and receptor proteolysis was observed. However, this proteolysis could not be definitively attributed to the actions of hCG. A purified receptor was subsequently prepared by hCG-affinity chromatography and analysed by SDS-PAGE with detection by autoradiography and silver staining. The purified receptor was found to have undergone proteolysis during the purification procedure, presumably following incubation with the hCG affinity matrix. Recent reports of the presence of homologous amino acid sequences in the active site of thioredoxin and the β-subunit of the gonadotropic hormones luteinizing hormone (LH) and follicle stimulating hormone (FSH), and subsequent demonstration of thioredoxin-like activity associated with these hormones, prompted an investigation into the possibility of thioredoxin-like activity associated with hCG. LH, FSH and hCG were all assayed for their ability to promote reactivation of reduced and denatured RNase. Although LH was shown to be capable of reactivating reduced RNase, the level of activity detected was significantly lower than that previously reported, whereas FSH and hCG were not found to be capable of this thioredoxin-like activity. These results suggested that the previously reported thioredoxin-like activity may be due to contamination of the hormone preparation, by the ubiquitous enzyme thioredoxin. The possibility of LH possessing intrinsic dithiol-disulphide interchange activity was investigated further using [3H]-iodoacetic acid. RNase/LH were incubated in an attempt to quench a dithiol intermediate. Preliminary results suggested that the presence of LH in this reaction increased the amount of protein radiolabelled, however, the isolation of a radiolabelled dithiol intermediate which could be conclusively identified as LH was not forthcoming. Furthermore the lack of RNase reactivation activity in hCG, suggests that the putative thioredoxin-like activity of LH, if intrinsic, may not be involved in receptor activation and/or signal transduction, as hCG and LH share the same receptor and should therefore have a similar mechanism of activation.
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Alehagen, Siw. "Fear pain stress hormones during labor /." Linköping : Univ, 2002. http://www.bibl.liu.se/liupubl/disp/disp2002/med730s.pdf.
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Al-Mana, D. "Ovarian steroid hormones and auditory function." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1386639/.
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Considerable anecdotal evidence and information from previous studies suggest that auditory function may be influenced by hormones. This thesis reviews in detail the potential role of hormones in modulating the auditory system and in the development of pathological conditions in the auditory system with an emphasis on the effect of the ovarian hormones. Ovarian steroids may influence auditory function directly through their receptors, which have been detected in the auditory system, or indirectly through their effects on the blood supply, the fluid electrolyte balance of the cochlea, and the neurotransmitters of the auditory system. Effects on other parts of the central nervous system connected to the auditory system may also be of importance. The aim of the study was to investigate whether physiological alterations in ovarian hormones in women with normal hearing, during the natural ovarian cycle and assisted conception treatment were associated with changes in auditory function at the cochlear and brain stem level, and whether these variations were not seen in men over a similar period of time. The auditory tests evaluated auditory function from the outer ear to the brainstem in both the afferent and efferent system. Hormone levels were assayed only in the female subjects at the same time as the auditory testing, four times during the ovarian cycle, or three times during the assisted conception treatment. Auditory tests were undertaken in the male subjects once a week for four consecutive weeks to correspond with the ovarian cycle measurements. A number of changes in auditory function were observed during the ovarian cycle and assisted conception treatment, and gender differences were noted. The OAE results may suggest either excitation of the cochlea with higher levels of oestrogen, or suppression of the cochlea with higher level of progesterone. The longer ABR latency following ovarian stimulation and in the follicular phase of the ovarian cycle is consistent with the inhibitory effect of neurosteroids on ABR associated with higher levels of oestrogen. The variation in auditory function were not observed in men.
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Farquharson, Roy G. "Fetal abstraction of placental steroid hormones." Thesis, University of Aberdeen, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328653.
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