Dissertations / Theses on the topic 'HPG axi'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'HPG axi.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
COTELLESSA, LUDOVICA. "THE INVOLVEMENT OF THE NOTCH PATHWAY IN THE GNRH NEURONS DEVELOPMENT." Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/814079.
Full textFord, Gemma. "Orexins and their involvement with the HPA axis." Thesis, University of Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409833.
Full textMarkopoulou, Kalypso. "HPA axis dysfunction in treatment resistant affective disorders." Thesis, King's College London (University of London), 2013. https://kclpure.kcl.ac.uk/portal/en/theses/hpa-axis-dysfunction-in-treatment-resistant-affective-disorders(3cac2a96-2cf1-43f8-a7e6-1c2fbc0b87b7).html.
Full textFarooq, Rai Khalid. "Implication fonctionnelle du récepteur P2X7 dans les mécanismes neuroinflammatoires associés à la dépression : étude préclinique." Thesis, Tours, 2012. http://www.theses.fr/2012TOUR4022/document.
Full textResearch work of this thesis was aimed to characterize role of IL-1 beta and P2X7 receptors in depressive illness. Results suggest that i stressed mice the behavioral and neurobiochemical changes are reversed by use of P2X7R antagonist. It is an evidence of antidepressant of these compounds
Dionne-Wilson, Laurence. "Serotonin as a Regulator of the Hypothalamic-Pituitary-Interrenal Axis in Rainbow Trout (Oncorhynchus mykiss)." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32163.
Full textQuillet, Raphaëlle. "Identification et caractérisation de nouveaux outils pharmacologiques sélectifs pour les différents récepteurs à peptides RF-amides." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAJ029.
Full textRF-amides (RFRPs, NPFF, QRFP, PrRPs, Kisspeptins) belong to a family of peptide characterized by a Arg-Phe-NH2 C-terminus highly conserved throughout the evolution. They target 5 G-protein coupled receptors (NPFF1R, NPFF2R, QRFPR, PrRPR, Kiss1R) and most studies highlight their roles in the modulation of various functions as pain and nociception, reproduction or metabolism. Nonetheless, the study of these systems is severely limited by the absence of pharmacological tools as selective antagonists. Thus, my PhD project consisted in the development of selective ligands to answer these questions, notably on NPFF1R, NPFF2R and Kiss1R receptors. Structure-Activity relationship studies highlighted the importance of Arg-Phe-NH2 signature for the activity of RF-amide peptides on their receptors. Introduction of modifications at N or C-terminus of Arg-Phe-NH2 dipeptide led us to the identification of a compound displaying high affinity, selectivity and antagonist activity for NPFF1R both in vitro and in vivo. This compound allowed us to identify the critical role played by NPFF1R in the secondary effects related to opiates administration, as hyperalgesia and analgesic tolerance. The involvement of NPFF1R was then confirmed in KO NPFF1R mice. Moreover, recent data suggest the importance of NPFF1R on hypothalamo-pituitary gonadotropic (HPG) axis of seasonal animals, and particularly of hamsters. Our antagonist allowed us to decipher the role of NPFF1R in RFRP-3-induced-LH release. For the first time, we also have characterized high affinity and selective compounds for NPFF2R that display partial agonist activity in vitro. Moreover, our work led to the in vitro characterization of a selective antagonist for Kiss1R, that complete the available tools to study the physiological functions modulated by this receptor and its ligand, the kisspeptine. Overall, my PhD thesis led to the characterization of several selective ligands for RF-amide receptors, and highlight the role of RFRP-3/NPFF1R system in the long-term effects associated to opiates
Kyle, Catriona Jane. "Contributions of cortisol and corticosterone to metabolic regulation in humans." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33042.
Full textVAN, HOOREN DANIELLA CHRISTINE. "GluR5 IS INVOLVED IN REGULATION OF THE HPA AXIS." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1080156678.
Full textPeric, Tanja <1982>. "Hair: a tool to evaluate the HPA axis activity." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6253/1/WHOLE_THESIS_PERIC.pdf.
Full textPeric, Tanja <1982>. "Hair: a tool to evaluate the HPA axis activity." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6253/.
Full textCouroussé, Thomas. "Rôle du transporteur de cations organiques 2 dans la réponse et la vulnérabilité au stress." Thesis, Paris 5, 2014. http://www.theses.fr/2014PA05P625.
Full textInteractions between genetic and environmental factors like exposure to stress play an important role in the pathogenesis of mood-related psychiatric disorders such as major depressive disorder. The polyspecific organic cation transporters (OCTs) were shown previously to be sensitive to the stress hormone corticosterone in vitro, suggesting these transporters might play a physiological role in the response to stress. During my PhD thesis I investigated the role of organic cation transporter 2 (OCT2) during stress and vulnerability to depression. OCT2 is expressed in several stress-related circuits in the brain and along the hypothalamic-pituitary-adrenocortical (HPA) axis. Genetic deletion of OCT2 in mice enhanced hormonal response to acute stress (156%) without altering adrenal sensitivity to adrenocorticotropic hormone (ACTH). As a consequence, OCT2-/- mice were potently more sensitive to the action of unpredictable chronic mild stress and developed a transient aggravation of depression-related behaviors involving spatial memory and social interaction. We showed that the functional state of the glycogen synthase kinase-3β (GSK3β) signaling pathway, highly responsive to acute stress, was altered in the hippocampus of OCT2-/- mice. In vivo pharmacology and Western blot experiments argue for increased serotonin tonus as a main mechanism for impaired GSK3β signaling in OCT2-/- mice brain during acute response to stress. Our findings identify OCT2 as an important determinant of the response to stress in the brain, suggesting that in man OCT2 mutations or blockade by certain therapeutic drugs could interfere with HPA axis function and enhance vulnerability to repeated adverse events leading to stress-related disorders
Khemissi, Wahid. "Etude de la dérégulation de l'axe HPA dans la création d'une résistance aux antidépresseurs et son implication dans la prolifération cellulaire et la neurogénèse hippocampique." Thesis, Tours, 2014. http://www.theses.fr/2014TOUR4030.
Full textOne-third of depressed patients included in clinical trials do not respond to antidepressant treatment. Dysregulation of the HPA axis and reduced hippocampal neurogenesis are the main factors of resistance to antidepressants. The objective of this work is to develop a model of resistance to antidepressant related to the HPA axis and to use this model to understand the underlying mechanisms. Our results suggest that dysregulation of negative feedback of the HPA axis at the beginning of the protocol can be a predictor of antidepressant treatment failure in depression. Our protocol shows that the failure of fluoxetine to induce antidepressant effects was associated with poor ability of compounds to stimulate cell proliferation in the dentate gyrus of the hippocampus. Further studies are needed to investigate the causal relationship between these phenomena
Nicola, Angela Cristina de [UNESP]. "Atuação das proteínas do relógio na senescência reprodutiva de ratas Wistar." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/152720.
Full textApproved for entry into archive by Ana Paula Rimoli de Oliveira null (anapaula@foa.unesp.br) on 2018-02-09T17:42:31Z (GMT) No. of bitstreams: 1 nicola_ml_dr_araca_int.pdf: 2735259 bytes, checksum: bcfc7217ff01dee64fa4ca1839e45c76 (MD5)
Made available in DSpace on 2018-02-09T17:42:31Z (GMT). No. of bitstreams: 1 nicola_ml_dr_araca_int.pdf: 2735259 bytes, checksum: bcfc7217ff01dee64fa4ca1839e45c76 (MD5) Previous issue date: 2017-12-12
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O envelhecimento é considerado processo multidimensional no qual fatores ambientais podem proteger ou, inversamente, agravar seus sinais, de maneira não linear, nos processos fisiológicos e neurocomportamentais. Durante este processo, os ritmos circadianos são interrompidos ou fragmentados com dissociação consequente dos ritmos circadianos do indivíduo e disfunções relacionadas ao relógio circadiano contribuem para o envelhecimento e para patologias a ele relacionadas. O objetivo deste estudo foi averiguar possível alteração temporal do sistema CLOCK no eixo HPG e a relação com às alterações hormonais que caracterizam a periestropausa. Foram utilizadas fêmeas adultas com ciclo estral regular (CD) na fase do diestro e fêmeas senis com ciclo estral irregular e persistência da fase do diestro (IDP). Para análises de expressão gênica dos clock genes Per2, Rev-erbα e Bmal1 no eixo HPG, foram utilizados punchs das regiões do NSQ, onde também foi analisado RNAm de AVP, APO e HMB destes animais, além da adenohipófise e ovários dos quais se extraiu o RNA para confecção do cDNA e realização de qPCR. A determinação da atividade neuronal vasopressinérgica no NSQ foi realizada por imunoistoquíca com dupla marcação para cFos e AVP em tecido previamente fixado com paraformaldeído. A concentração plasmática de gonadotrofinas foi determinada por radioimunoensaio. De modo geral, os animais IDP revelaram alterações no perfil de expressão gênica durante o fotoperíodo, com redução de amplitude, deslocamento/desalinhamento de fase e ausência de antifase. O NSQ de animais IDP apresentou menor expressão de Rev-erbα e maior expressão de RNAm para AVP em relação ao grupo CD. A quantificação relativa de Bmal1 foi semelhante em ambos os grupos e não houve diferenças entre grupos na expressão de Per2. Na APO, animais IDP apresentaram maior expressão de Per2 e menor quantidade de RNAm para Rev-erbα. No HMB observou-se menor expressão para Per2 e Rev-erbα e maior expressão de Bmal1 nas fêmeas IDP. Per2 e Bmal1 na adenohipófise tiveram menor expressão que o gene Rev-erbα no grupo senil e o ovário destes animais revelou maior expressão para Per2 e Rev-erbα, em comparação com os animais CD. As concentrações plasmáticas de FSH foram maiores nas fêmeas com ciclo irregular (2,05 ± 0,44 ng/mL), principalmente durante a fase clara, assim como o LH (0,24 ± 0,07 ng/mL), cujos maiores valores foram encontrados durante a fase escura e com perfil semelhante ao RNAm de AVP. As imunomarcações revelaram alta atividade vasopressinérgica na porção dorsomedial do NSQ das fêmeas IDP. Juntos estes dados permitem concluir que há desarranjo na expressão temporal dos genes Per2, Rev-erbα, Bmal1 que compõem a maquinaria molecular do relógio circadiano, bem como de RNAm para AVP no NSQ, de fêmeas Wistar na periestropausa. Além disso, a maior atividade neuronal vasopressinérgica e a ausência de oscilação de Rev-erbα e Bmal1 no NSQ destes animais, comprometem a correta comunicação do relógio central do NSQ com o eixo HPG, inviabilizando a manutenção da fertilidade feminina e contribuindo para a senescência reprodutiva.
Aging is considered a multidimensional process in which environmental factors can protect or, conversely, aggravate its signals, non-linearly, in physiological and neurobehavioral processes. During this process, circadian rhythms are disrupted or fragmented with consequent dissociation of the individual's circadian rhythms and circadian clock-related dysfunctions contribute to aging and related pathologies. The objective of this study was to investigate possible temporal alteration of the CLOCK system in the HPG axis and the relation with the hormonal changes that characterize periestropause. Adult females with regular estrus cycle in the diestrous phase (RD) and old females with irregular estrous cycle and persistent diestrous phase (IPD). For analyzes of the gene expression of the genes Per2, Rev-erbα and Bmal1 in the HPG axis, punchs from the NSQ regions were used, where AVP, POA and MBH RNAm from these animals were also analyzed, as well as the adenohypophysis and ovaries from which they were extracted the RNA for cDNA production and qPCR performance. The determination of the vasopressinergic neuronal activity in the NSQ was performed by immunohistochemical with double labeling for cFos/AVP in tissue previously fixed with paraformaldehyde. The plasma concentration of gonadotrophins was determined by radioimmunoassay. In general, the IPD animals show alterations in the gene expression profile during the period analyzed, with amplitude reduction, phase shift / misalignment and absence of antiphase. The NSQ of IPD animals presented lower expression of Rev-erbα and higher RNAm expression for AVP than RD group. The relative quantification of Bmal1 was similar in both groups and there were no differences between groups in the expression of Per2. In PAO, IPD animals showed higher expression of Per2 and less amount of RNAm for Rev-erbα. MBH showed lower expression for Per2 and Rev-erbα and higher Bmal1 expression in IPD females. Per2 and Bmal1 in the adenohypophysis had lower expression than the Rev-erbα gene in the old group and the ovary of these animals showed higher expression for Per2 and Rev-erbα, in related to to the RD animals. Plasma concentrations of FSH were higher in females with irregular cycle (2.05 ± 0.44 ng / mL), mainly during the light phase, as well as LH (0.24 ± 0.07 ng / mL) whose values were found during the dark phase and with a profile similar to AVP RNAm. Immunolabeling demonstrated high vasopressinergic activity in the dorsomedial portion of the NSQ of the IPD females. Together these data allow us to conclude that there is a breakdown in the temporal expression of the Per2, Rev-erbα, Bmal1 genes that make up the molecular machinery of the circadian clock, as well as RNAm for AVP in NSQ of Wistar females in peri-masterpause. In addition, the increased vasopressinergic neuronal activity and the absence of Rev-erbα and Bmal1 oscillation in the NSQ of these animals compromise the correct communication of the central clock of the NSQ with the HPG axis, making it impossible to maintain female fertility and contributing to reproductive senescence.
Alves, Luana Maria Silva. "Participação de receptores ER e ER na ativação do eixo hipotálamo-hipófise-adrenal por estresse hemorrágico." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/17/17134/tde-06012016-132149/.
Full textDepending on the stressors category, specific neural pathways are involved and different responses can be selected. It has been reported in the literature that estrogen (E2 ) can affect hypothalamus pituitary adrenal (HPA) axis activity through its receptors type (ER) and (ER). Moreover, there is evidence that E 2 has protecting properties after hemorrhagic shock. The aim of this work was to assess the participation of ER and ER on HPA axis activity during hemorrhagic stress. It was used ovariectomized Wistar rats that received s.c. injections of: DMSO (vehicle), PPT (ER agonist) or DPN (ER agonist), during 3 days. In the second day the rats were catheterized for serial blood collect in the next morning. Animals received (control) or not (hemorrhagic) immediate reposition with same volume of isotonic saline. The hormones corticosterone (CORT), oxytocin (OT) and vasopressin (AVP) were measured by radioimmunoassay. At the end of the experiment, animals were perfused and their brains were processed for immuno-histochemistry for FOS, tyrosine hydroxylase (TH) and corticotropin releasing hormone (CRH). In vehicle treated animals, the gradual hemorrhage enhanced CORT, OT and AVP secretion, TH activated neurons expression in A1C1 and FOS expression in mpPVN. PPT decreased plasma CORT in control situation acting on LC and mpPVN, and also after hemorrhage acting on LC, NTS, A1C1 and mpPVN. DPN reduced plasma CORT only after hemorrhagic stress acting on LC, A1C1 and mpPVN. PPT blocked the increase of OT secretion and increased AVP secretion, after hemorrhage. The agonist DPN reduced OT and increased AVP levels, despite hemorrhage. In conclusion: E2 can exert an inhibitory effect on CORT basal secretion only through ER action on LC and mpPVN; CORT secretion increases after gradual moderate hemorrhage and E2 inhibit this secretion through ER action on LC, NTS, A1C1 and mpPVN, as well through ER action on LC, A1C1 and mpPVN.
Minni, Amandine. "Rôle de la Transcortine (CBG) dans la variabilité des réponses de stress." Thesis, Bordeaux 2, 2011. http://www.theses.fr/2011BOR21875/document.
Full textA great diversity in the adaptive response to stress is observed between individuals favoring a variable sensitivity to face stressors and leading to a vulnerability to develop various disorders and diseases. This diversity is due to the characteristics of each individual, as determined by the genetic background in interaction with environmental factors. Genetic studies conducted in the laboratory demonstrated that the Cbg gene is an important candidate influencing stress responses. The team then developed a mouse model deficient for the gene Cbg (total k.o.). CBG is a plasma glycoprotein responsible for the bioavailability and the transport of glucocorticoids, the final products of the HPA axis, to their target.Using this original model, the objective of my thesis was to study the functional consequences of CBG deficiency on responses to stress exposure. We have analyzed the activity and reactivity of the HPA axis and the emotional behaviors of males and females k.o. Cbg in resting conditions, acute stress and in a context that mimics the effect of a Western life style (modeled by a high fat diet, associated with chronic stress). We present an unique mouse model of glucocorticoid hyposignaling in response to stress associated with behavioral responses slowed down at the emotional and cognitive levels. Overall, this work contributes to place CBG and its gene as major actor of individual variability to stress
Iliadis, Stavros I. "Personality and the HPA-axis in Association with Postpartum Depression." Doctoral thesis, Uppsala universitet, Obstetrik & gynekologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-274956.
Full textKalyani, Manu. "Interaction between Prolactin and the Hypothalamic-Pituitary-Adrenal (HPA) axis." Miami University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=miami1397233916.
Full textWiklund, Liselotte. "Premenstrual Dysphoric Disorder : A Review of Neural and Cognitive Changes in Women with PMDD." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-14302.
Full textCanet, Geoffrey. "Rôle central des glucocorticoïdes et de leurs récepteurs dans l’étiologie de la Maladie d’Alzheimer." Thesis, Montpellier, 2020. http://www.theses.fr/2020MONTT019.
Full textAlzheimer's disease (AD) is characterized in the brain by the aggregation of β-amyloid peptides (Aβ) from the cleavage of the amyloid precursor protein (APP), and by the hyperphosphorylation of the Tau protein. In AD, cognitive deficits are associated with an early dysregulation of the endocrine stress axis (hypothalamic-pituitary-adrenal axis or HPA), the consequent overproduction of glucocorticoids (GC) and the alteration of their receptors (GR). Numerous studies demonstrate the involvement of GR in AD, particularly via the increase of Aβ production and the hyperphosphorylation of Tau. In an acute model of AD (icv injection of an oligomeric solution of oAβ25-35 peptides in rat), we observed a dysregulation of the HPA axis, associated with a set of cellular alterations reminiscent of the human pathophysiology. There is a vicious cycle in which the pathology induces an overproduction of GC, which in turn potentiates AD. The objective of my thesis was therefore to break this vicious cycle using a new class of molecules acting as selective GR modulators (sGRm). The sGRm have the particularity to abrogate the pathological effects of GR, while retaining their physiological signaling. In a first study, we showed in the oAβ25-35 model that a sGRm (CORT113176) reverses in the hippocampus all the alterations induced by amyloid toxicity (short-term memory deficits, high plasma GC levels, synaptic deficits, neuroinflammation, apoptosis and increased Aβ synthesis). In a second study, we performed analyzes in the prefrontal cortex. This structure of interest in AD is also very rich in GR, suggesting that this region is very sensitive to deregulation of the HPA axis. Here, we used sGRm as a tool to characterize the involvement of GR in a number of intracellular signaling pathways. We notably observed the GR phosphorylation state, their chaperones (HSP90 / 70), the balance between the amyloidogenic and non-amyloidogenic pathways or the main enzymes involved both in GR and Tau phosphorylation (GSK-3β , Cdk5, Calpain-1, Fyn). GR appeared to be involved in numerous processes associated with oAβ25-35 toxicity, and CORT113176 reversed this toxicity, highlighting the central role played by GR in the pathophysiology of AD. In a final study, following all of these initial results, and in order to validate the therapeutic potential of CORT113176, we tried to bring the proof of concept via two complementary approaches. Firstly, we tested the robustness of the treatment with the sGRm in the oAβ25-35 model in order to observe whether breaking the vicious circle by restoring the physiology of the HPA axis, the GC and the GR could help at long-term to fight against the pathology. The first results showed that CORT113176 reversed at long-term the amyloid toxicity on the parameters measured previously, but also seems to reverse Tau hyperphosphorylation. Finally, we wanted to confirm the therapeutic interest of breaking the vicious circle in a transgenic mouse model of AD, the J20 mouse (mutated human APP transgene). In 9-month-old animals, CORT113176 again appeared to reverse a large number of markers associated with AD. All of these results place the HPA axis and GR at the heart of the pathophysiology of AD, which could make the link between amyloid toxicity and Tau hyperphosphorylation. This work also highlights the promising approach represented by sGRm which break the vicious circle between the deregulation of the HPA axis and amyloid toxicity, by restoring the primary role of GC and GR in the maintenance of homeostasis
Heinzmann, Jan-Michael. "Central and peripheral aspects of hypothalamic-pituitary-adrenal (HPA) axis dysfunction." Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-150032.
Full textGallagher, Peter. "Spatial memory processes in bipolar depression : neuropsychological and HPA axis correlates." Thesis, University of Newcastle Upon Tyne, 2011. http://hdl.handle.net/10443/1108.
Full textPereira, Ana Rita Salgueiro. "HPA axis function and episodic memory loss in early Alzheimer disease." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/12509.
Full textAlzheimer’s disease (AD) is a brain neurodegenerative disease leading to progressive loss of memory and intellectual abilities. It is characterized by the appearance of amyloid-β oligomers (Aβ), which then aggregate into plaques, progressive appearance of neurofibrillary tangles composed of hyperphosphorylated tau, synaptic impairment and neuronal death. The hippocampus, a key structure responsible for memory encoding, is the first brain region affected in AD leading to early episodic memory loss. Aβ accumulation seems to have an important role in triggering chronic stress in AD, compromising the hypothalamic-pituitary-adrenal (HPA) axis function and the structures involved in its regulation, notably the hippocampus. The purpose of the present study was to evaluate the HPA axis function and episodic-like memory in a model of AD, the Tg2576 mice, in the early phase of the pathology, which was defined in these mice at about 4 months of age. To study the HPA axis function, corticosterone, the main stress hormone, was quantified by ELISA at the onset of light phase, at the onset of dark phase and after inducing the negative feedback with a dexamethasone supression test. Hippocampal glucorticoid receptors (GRs) were also quantified by Western blot. Tg2576 mice showed impairment in HPA axis, characterized by an increase in corticosterone at the onset of active phase and an absence in the negative feedback response induced by dexamethasone. Also, hippocampal GRs are increased and seems to fail in the downregulation of the stress response mediated by the HPA axis. To evaluate episodic-like memory, an object recognition task was conducted, which combines the ability to remember the ‘what, when and where’ components of an event. A deficit in the ‘where’ component of this type of memory was observed in Tg2576 mice. An in vivo treatment with the GR antagonist RU486 was then applied to evaluate if blocking GR function could reverse this deficit. Our first results suggest that blocking GR function can prevent this memory deficit in Tg2576 mice. These data demonstrate that corticostesterone levels, and thus stress signaling, are increased in the early phase of AD in these mice, due to dysfunction of the HPA axis. Furthermore, this altered signaling, via GRs, probably contributes to the early episodic memory deficits observed in these mice. These data strongly support our hypothesis that elevated stress is an environmental factor contributing to the onset of AD neuropathology.
A Doença de Alzheimer (DA) é uma doença neurodegenerativa do tecido cerebral que leva à perda da memória e das propriedades intelectuais. É caracterizada pelo aparecimento de oligómeros de amilóide-β (Aβ) que depois se agregam em placas, aparecimento progressivo de agregados neurofibrilares constituídos por proteína tau hiperfosforilada, alterações sinápticas e morte neuronal. O hipocampo, uma estrutura chave responsável pela codificação da memória, é a primeira região cerebral afectada na DA levando numa fase precoce, à perda da memória episódica. A acumulação de Aβ parece ter uma função importante no desencadeamento de stress crónico na DA levando ao comprometimento da função do eixo HPA e das várias estruturas envolvidas na sua regulação, nomeadamente o hipocampo. Neste estudo pretendeu-se estudar a função do eixo HPA e avaliar a memória episódica usando um modelo transgénico da DA, o ratinho Tg2576, numa fase precoce da doença de Alzheimer, definida neste modelo por volta dos 4 meses. Os estudos relativos à função do eixo HPA foram feitos através da quantificação de corticosterona, a hormona principal no stress, por teste ELISA na fase de repouso, na fase activa e após teste de supressão pela dexametasona. Quantificaram-se ainda os receptores aos glucocorticoides (RGs) no hipocampo por western blot. Os ratinhos Tg2576 mostraram um comprometimento do eixo HPA, caracterizada pelo aumento de corticosterona no ínicio da fase activa e ausência de regulação negativa induzida pela dexametasona. Ainda, os RGs estão aumentados e mostram comprometimento na regulação negativa induzida no eixo HPA. Para avaliar a memória episódica foi efectuado um teste de reconhecimento de objectos que combina a capacidade de recordar o ‘quê, quando e onde’ de um evento. Os ratinhos Tg2576 apresentaram um deficit na componente ‘onde’ deste tipo de memória. Foi em seguida aplicado um tratamento in vivo com um antagonista dos RGs (RU486) para avaliar se bloqueando a função dos RGs se poderia reverter o deficit observado. Os nossos primeiros resultados revelam que o bloqueia dos RGs pode prevenir o deficit na memória episódica. Assim este trabalho mostrou que os ratinhos Tg2576 apresentam uma perturbação ao nível do eixo HPA e da sua regulação pelos RG do hipocampo, traduzidos por um nível de stress aumentado, e perturbação ao nível da memória episódica. Este trabalho mostra que o nível de stress está aumentado numa fase muito precoce da DA neste ratinho devido à disfunção do eixo HPA. Para além disso, a alteração nesta sinalização mediada pelos RGs, contribui provavelmente para os deficits precoces na memória episódica observados neste ratinho. Estes resultados suportam a nossa hipótese de que o stress é um factor de risco muito importante no desenvolvimento precoce da neuropatologia na doença de Alzheimer.
Radtke, Karl [Verfasser]. "Early adversities and epigenetic modifications of HPA-AXIS genes / Karl Radtke." Konstanz : Bibliothek der Universität Konstanz, 2017. http://d-nb.info/1124780823/34.
Full textFinn, David Patrick. "Monoamines and the neuroendocrine response to stress : the role of imidazoline I₂ binding sites and α₂-adrenoceptors." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340303.
Full textHenderson, Dallas Wade. "Stress Response and Acclimation in the Adult Turquoise Killifish Nothobranchius furzeri." OpenSIUC, 2016. https://opensiuc.lib.siu.edu/theses/1941.
Full textZhang, Xiaowei. "Application of toxicogenomic approaches to study chemical-induced effects on the hypothalamic-pituitary-gonadal (HPG) axis of the Japanese medaka (Oryzias latipes)." Diss., Connect to online resource - MSU authorized users, 2008.
Find full textTitle from PDF t.p. (viewed on Mar. 30, 2009) Includes bibliographical references. Also issued in print.
Evanson, Nathan K. "Rapid regulation of the hypothalamus-pituitary-adrenal axis by glutamate and glucocorticoids." Cincinnati, Ohio : University of Cincinnati, 2008. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1227289026.
Full textAdvisor: James Herman PhD (Committee Chair), Randall Sakai PhD (Committee Member), Stephen Woods PhD (Committee Member), David D'Alessio MD (Committee Member), Yvonne Ulrich-Lai PhD (Committee Member). Title from electronic thesis title page (viewed Feb. 9, 2009). Keywords: HPA axis; glutamate; cannabinoids; nongenomic; glucocorticoids. Includes abstract. Includes bibliographical references.
Riel, Els van. "Dysregulation of the HPA-axis implications for serotonin responses in the hippocampus /." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2004. http://dare.uva.nl/document/73464.
Full textSchreckenbach, Monika [Verfasser]. "Dissociative stress response corresponds with downregulation of the HPA-axis / Monika Schreckenbach." Konstanz : KOPS Universität Konstanz, 2019. http://d-nb.info/1198113375/34.
Full textSeale, Josephine Victoria. "Gonadal steroids : modulators of hypothalamo-pituitary-adrenal (HPA) axis activity throughout life." Thesis, University of Bristol, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414189.
Full textShin, Andrew Changhun. "Unveiling diet-induced obesity leptin insensitivity and dysregulation of the HPA axis /." Diss., Connect to online resource - MSU authorized users, 2008.
Find full textBakirtzi, Georgia. "Epigenetic regulation of POMC : implications for the hypothalamic-pituitary-adrenal (HPA) axis." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/9455/.
Full textAlves, Luana Maria Silva. "Efeitos de estrógeno e de progesterona na atividade basal do eixo hipotálamo hipófise adrenal." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/17/17134/tde-03082015-135704/.
Full textThere is evidence for a bidirectional communication between HPA and HPG axis involving different structures, however the involved mechanisms are poorly known. Stress situations may alter the reproductive function, and gonadal steroids may modify the stress response. The aim of this study was verify if estrogen (E 2) and progesterone (P 4 ) can alter the basal activity of hypothalamic-pituitary-adrenal axis, analyzed by corticosterone (CORT) and P 4 secretions and by mineralocorticoid and glicocorticoid receptors (MR and GR, respectively) expression at HPA axis central feedback sites. Adult female Wistar rats were kept in 12h light-dark cycle and had free access to food and water. The estrous cycle was monitored by vaginal smears and the luteinizing hormone dosage was done to confirm proestrus. Six samples of blood were collected by jugular cannula, during the afternoon (13-18h), of the following groups: ovariectomized (OVX), proestrus controls, treated with E 2 or P 4 antagonists (tamoxifen or RU486, respectively), or with both, and treated with antagonists vehicle. The plasm was stored for hormonal dosages by radioimmunoassay. After the last blood sample, animals were anesthetized, perfused, and the brains were removed and processed for immunofluorescence to analyze MR and GR expression at ventral hippocampus CA 1 and subiculum, and GR expression at paraventricular nucleus (PVN). The results showed that: LH secretion confirmed the proestrus; CORT basal secretion was not altered by injections neither by ovariectomy; there was a CORT and a P4 secretion peak at 14h in all experimental groups, E 2 and P 4 antagonists did not modify the CORT total secretion, however RU486 increased (at 13 and 15h) and tamoxifen reduced (at 15h) CORT levels, another P4 secretion peak in the late afternoon (17-18h) was blocked by ovariectomy and tamoxifen, but enhanced by RU486, the P 4 second peak did not occur in rats treated with both tamoxifen and RU486, there were no changes in the number of neurons expressing GR and MR at ventral hippocampus CA 1 and subiculum neither of GR expressing neurons at PVN. In conclusion, our results indicate that: E2 and P 4 can have antagonistic effects over basal CORT secretion; stimulatory and inhibitory, respectively; the P 4 secretion peaks have different origins, the first (14h) is adrenals and the second (17-18h) is ovarian: E2 stimulates ovarian P 4 secretion in the proestrus afternoon; E 2 and P 4 do not alter the number of neurons that express MR and GR at HPA axis feedback sites, but one can not exclude the possibility that they alter the activity of these neurons.
Nayar, Shweta. "NOCICEPTIN/ORPHANIN FQ (N/OFQ) REGULATION OF THE STRESS RESPONSE: INTERACTION BETWEEN PROLACTIN AND THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS." Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1382509698.
Full textEngman, Robin. "HPA* Used With a Triangulation-Based Graph." Thesis, Blekinge Tekniska Högskola, Institutionen för kreativa teknologier, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5630.
Full textKatopodis, Angela. "Gender differences in the response of the HPA-axis to alcohol and stress." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82262.
Full textBerg, Ingrid Helene. "The Relationship Between Insomnia and CFS/ME : The HPA Axis as a Mediator." Thesis, Norges teknisk-naturvitenskapelige universitet, Psykologisk institutt, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-25191.
Full textFaturi, Claudia de Brito [UNIFESP]. "Consequências da privação materna para o comportamento tipo-ansioso: participação do eixo hipotálamo-pituitária-adrenal e do sistema de neurotransmissão GABAaérgico." Universidade Federal de São Paulo (UNIFESP), 2009. http://repositorio.unifesp.br/handle/11600/9250.
Full textAssociação Fundo de Incentivo à Psicofarmacologia (AFIP)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Alguns estudos pré-clínicos têm demostrado que eventos adversos na infância e adolescência representam um fator de vulnerabilidade para o surgimento de transtornos psiquiátricos na idade adulta, e que a redução da resiliência à eventos estressantes deve desempenhar um papel importante neste fenômeno. As manipulações em animais de laboratório, como a privação materna (PM) por 24 h durante o período de hiporresposividade ao estresse (PHRE), podem ser um instrumento útil para a compreensão de como os eventos no período precoce do desenvolvimento resultam em alterações comportamentais e da atividade do eixo Hipotálamo-Pituitária-Adrenal (HPA) na idade adulta. Alguns autores têm observado que a PM, quando imposta no 3° dia de vida (antes do início) ou no 11° dia (no vale) do PHRE, resulta em padrões de atividade do eixo HPA distintos. A PM no 3° dia induz à hiperatividade do eixo, enquanto que no 11° dia, resulta na hipoatividade, alterações estas observadas em animais jovens. Assim, os principais objetivos do presente trabalho foram os de estudar como a PM afetaria a atividade do eixo HPA durante o PHRE, e verificar se essas alterações teriam conseqüências duradouras. Os resultados mostraram que os efeitos da PM na liberação de ACTH mantiveram o mesmo padrão de atividade relatado na adolescência, ou seja, hiperresponsividade no grupo submetido à PM no 3o dia de vida e hiporresponsividade no grupo submetido à mesma manipulação no 11o dia de vida. No entanto, essa alteração não se refletiu na liberação da corticosterona (CORT), pois não se observou diferença na secreção deste hormônio entre os grupos. Além disso, a PM não alterou a liberação de CORT em resposta ao Teste de supressão à Dexametasona, indicando que não houve alterações no sistema de retroalimentação negativa no nível hipofisário do eixo HPA. A PM afetou o comportamento do tipo ansioso nos animais de ambos os grupos PM, sendo que tal alteração parece não ter sido mediada por mudanças na densidade do sítio benzodiazepínico do receptor GABAA. Os resultados indicaram que, embora a PM não leve a alterações permanentes na secreção da corticosterona, este pode ser um modelo animal interessante para se estudar o substrato neurobiológico que faz com que um evento adverso durante o desenvolvimento aumente a vulnerabilidade aos transtornos relacionados à ansiedade.
Adverse events in childhood have been associated to the development of psychopathologies, such as depression and anxiety disorders. In rats, stressful events during neonatal period, like 24h Maternal Deprivation (MD), may be an interesting tool to understand how stress during early life leads to changes in behavior and stress response in adulthood. According to some studies, MD on the 3rd day (MD 3-4) or 11th day (MD 11- 12) of life results in opposite changes in the activity of the Hypothalamus-Pituitary- Adrenal (HPA) axis, i.e., hyper and hyporresponsiveness, respectively. Since in human beings psychopathologies has been related to impairment in resilience to stress the aim of this work was to investigate whether MD leads to long lasting changes in HPA axis functioning and differential behavioral features in animal models of anxiety. The results obtained indicate that only the ACTH release presented the pattern we hypothesized. Conversely the corticosterone (CORT) plasmatic levels do not reflect this pattern. Moreover, MD did not affect the CORT release in response to the Dexamethasone Suppression Test, indicating that there are MD did not alter the negative feedback system. Although MD did not lead to convincing alteration to CORT levels it did change anxiety-like behavior in the group MD 11-12. However this behavioral change did not seem to be mediated by expression of benzodiazepine site in GABAA receptors. The results indicate that even though the MD procedure does not lead to consistent changes in the peripheral component of the HPA axis it could still be an interesting animal model to study the neurobiological underpinnings of how adverse events in early life increase the vulnerability to psychopathologies.
FAPESP: 2006/06415-4
TEDE
BV UNIFESP: Teses e dissertações
Duncan, Peter James. "Regulation of murine corticotroph cell excitability." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/17965.
Full textFigueiredo, Danielle. "Influence of Life Events on the Stress Response in Healthy Children and Adolescents." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/41220.
Full textTahera, Yeasmin. "Modulation of the HPA axis alters the sensitivity of the cochlea to acoustic trauma /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-932-7/.
Full textBaiamonte, Matteo. "Developmental ethanol exposure and its impact on behaviour and HPI axis activity of zebrafish." Thesis, Queen Mary, University of London, 2015. http://qmro.qmul.ac.uk/xmlui/handle/123456789/7873.
Full textMichailidou, Zoi. "Modelling altered glucocorticoid sensitivity : from HPA axis to metabolic abnormalities in mice and humans." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/2689.
Full textDi, Rollo Emma Margaret. "Role of 5α-reductase type 1 in modifying anxiety, appetite and the HPA axis." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/10026.
Full textSeltzer, Molly K. "DISCRIMINATION, HPA-AXIS ACTIVITY, AND RACIAL IDENTITY IN AFRICAN-AMERICAN ADOLESCENT RISK FOR DEPRESSION." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/536392.
Full textPh.D.
Culturally relevant models of social, psychological, and biological risk for depression in African American youth have long been called for, to account for unique risk factors they experience (e.g., discrimination) and that incorporate culturally specific protective assets (e.g., racial identity). Yet few studies have directly examined physiological mechanisms that might mediate the connection between discrimination and depression, nor the way in which cultural assets may attenuate such pathways. The present study is an explicit test of a model of risk for depression that integrates discrimination during adolescence, the hypothalamic-pituitary-adrenal (HPA)-axis as a biological regulator of social stress, and dimensions of racial identity as potential moderators of HPA-axis dysregulation. A subsample of 109 African-American adolescents (age 11-17; M = 12.88, SD = 1.11) who completed a social stress paradigm was drawn from a larger longitudinal study on risk for depression. Utilizing a longitudinal design, variables were collected on prior discrimination experience, cortisol reactivity and recovery during the stress paradigm, racial identity at the time of the stress paradigm, and concurrent and prospective depressive symptoms. A series of regression analyses and t-tests were conducted to test the impact of discrimination on cortisol regulation and depressive symptoms, and the moderating role of racial identity in the relation between cortisol regulation and depressive symptoms. Youth who reported discrimination experienced higher mean levels of depression. Discrimination was not related to cortisol regulation, nor were racial identity dimensions significant moderators in risk for depressive symptoms. This study, the first to explicitly test a culturally relevant model of risk for depression, points to the importance of capturing nuances in stress reactivity to discrimination in explicit tests of culturally-relevant models of depression in minority youth.
Temple University--Theses
Sautron, Valerie. "Biologie intégrative des réponses de stress et robustesse chez le porc." Thesis, Toulouse, INPT, 2016. http://www.theses.fr/2016INPT0086/document.
Full textThis PhD thesis is part of the SUSoSTRESS project. This ANR funded project aims at improving the knowledge about molecular and genetic mechanisms underlying inter-individual variability in stress responses. Longitudinal data were collected at several biological levels on a porcine population (Large White). This work is structured in 2 parts. The first part is built around clinical and transcriptomic longitudinal data analyses collected before and after 2 types of stress factors : ACTH and LPS injection. The aim of this contribution is to develop a functional model describing all sources of genetic variation in the HPA axis activity and in stress responses in our study population.More precisely, it aims at defining a model describing the different biological stress responses and the influence of genetic variations in order to identify the most efficient selection levers according to selection goals. This work allowed for the identification of 65 differentially expressed genes during stress responses. Among them, 8 genes were highly linked to cortisol (the main stress hormone) through NR3C1 (glucocorticoid receptor (GR)). These genes are potential biomarkers and can be communicated to breeders as selection levers for a better trade-off between production and robustness traits in farmanimals. The second part is built around the development of a statistical tool suited for the data integration of repeated omicmeasurements with a real target variable.We introduce the "multiway-SIR" approach which extends the dual-STATIS (an approach to study 3-way datasets) method to the SIR framework (a semi-parametric regression model that can be used in an exploratory way). This method is illustrated on clinical data from the ACTH experiment. It allows for the exploration of the link between clinical variable response over time and inter-individual variability in the cortisol response to an ACTH injection
Čulig, Luka. "Effets de l'augmentation de la neurogénèse adulte dans un modèle murin écologique de dépression." Thesis, Tours, 2017. http://www.theses.fr/2017TOUR4021.
Full textMajor depressive disorder (MDD) is a complex and heterogeneous disorder hypothesized to be associated with alterations in brain circuitry, dysregulations of the hypothalamic–pituitary–adrenal axis and impairments in adult hippocampal neurogenesis (AHN). Multiple lines of evidence point to the involvement of AHN in mood and anxiety disorders, leading to the formation of the “neurogenesis hypothesis”, which postulates that adult-born hippocampal neurons are involved in the etiology and treatment efficacy of MDD. The purpose of this study was to determine the role of adult-born neurons after the onset of stress exposure and the mechanism that underlies the observed results. Our results suggest that increasing neurogenesis is sufficient to buffer against the effects of chronic stress on certain behavioral and endocrine levels and thus to display antidepressant-like effects, both behaviorally and physiologically. Adult-born neurons might have exerted some of their effects via the anteromedial division of the bed nucleus of the stria terminalis (BSTMA)
Brureau, Anthony. "Effet de l’injection intracérébroventriculaire du peptide Aβ 25-35 chez le rat mâle adulte au cours du temps : toxicité amyloïde et implication dans la dérégulation de l’axe Hypothalamo-hypophyso-surrénalien." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20079.
Full textAlzheimer's disease (AD) is characterized by neurofibrillary tangles and seniles plaques. The major component of senile plaques is the amyloid-β peptide (Aβ). In a first part of this thesis, we characterized the time course toxicity effect of the Aβ25-35 intracerebroventricular (icv) injection in the rat brain. We particulary demonstrated, that only one injection induced memories impairments at short and long term which persisted six weeks after the icv injection. We also shown, a sustain astrogliosis and microgliosis, oxidative stress, apoptotics processes in the differents brain structure of interest.In a second part of this thesis, we characterized the time course impact of Aβ25-35 on hypothalamo-pituitary-adrenal axis during the time. First, we demonstrated an the hyperactivity of the axis, which is characterized by modifications of hormonal concentration associated with modification of the expression and localization of glucocorticoids (GC) receptors. We also demonstrated Aβ25-35 an anxious behavioural in animals. Nevertheless, the functionality of negative feedback is not modified. However, Aβ25-35 injection modify the HPA axis reactivity after acute stress. In conclusions, we shown, in a pathomimetic model of AD that the Aβ25-35 toxicity modifes the reactivity and the functionality of HPA axis, that could be partly involved in the pathophysiology of AD
Neigh, Gretchen N. "Neural and immune changes that occur following psychological and physical stressors." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1092752738.
Full textDocument formatted into pages; contains 258 p. Includes bibliographical references. Abstract available online via OhioLINK's ETD Center; full text release delayed at author's request until 2005 Aug. 17.
Salander, Katarina. "Early life stress and psychopathology : The effects of early life stress on brain development: Implications for psychopathology." Thesis, University of Skövde, School of Humanities and Informatics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-3475.
Full textSeveral studies have shown that children who grow up under adverse care giving conditions are prone to develop a broad spectrum of different problems, ranging from mild depression to severe psychosomatic pathology later in life. A carefully treated child develops a different attachment strategy and biochemical response than a maltreated child. Early adverse events seem to program the stress response to become either over or under reactive which in turn have the potential to alter brain development. Major consequences include reduced plasticity and abnormal frontal lobe activity. This review further investigates the emotional and cognitive development in children exposed to early life abuse or neglect, trying to get a comprehensive picture of different symptoms that might contribute to later psychopathology.