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Hypothalamic-pituitary-adrenal axis responsivity to an acute novel stress in female rats subjected to the chronic mild stress paradigm.
Traslaviña, Guillermo A Ariza; Torres, Fernanda Pedrosa; de Barcelos Filho, Procópio Cleber Gama; Lucio-Oliveira, Fabiana; Franci, Celso Rodrigues.
Afiliação
  • Traslaviña GAA; Ribeirão Preto Medical School, Department of Physiology, University of São Paulo, 14049-900 Ribeirão Preto, SP, Brazil.
  • Torres FP; Ribeirão Preto Medical School, Department of Physiology, University of São Paulo, 14049-900 Ribeirão Preto, SP, Brazil.
  • de Barcelos Filho PCG; Ribeirão Preto Medical School, Department of Physiology, University of São Paulo, 14049-900 Ribeirão Preto, SP, Brazil.
  • Lucio-Oliveira F; Ribeirão Preto Medical School, Department of Physiology, University of São Paulo, 14049-900 Ribeirão Preto, SP, Brazil.
  • Franci CR; Ribeirão Preto Medical School, Department of Physiology, University of São Paulo, 14049-900 Ribeirão Preto, SP, Brazil. Electronic address: crfranci@fmrp.usp.br.
Brain Res ; 1723: 146402, 2019 11 15.
Article em En | MEDLINE | ID: mdl-31446015
The chronic mild stress (CMS) paradigm is the most frequently investigated animal model for major depression. The hypothalamic-pituitary-adrenal (HPA) axis participates in the generation of depressive symptomatology. We examined whether the depression-like state induced by CMS is associated with immediate changes in HPA axis activation in response to a novel acute stress and whether this response could be modified by hormonal status. Adult female Wistar rats were ovariectomized and received estrogen or vehicle pellets. After 2 weeks, rats were subjected to CMS (or control) conditions for 2.5 or 4.5 weeks. Rats were subsequently subjected to restraint stress for 1 h, and plasma corticosterone (CT) levels were determined before (2:00 p.m.) and after acute stress induction (3:00 and 4:00 p.m.). CT levels and FOS expression were measured in the medial parvocellular subdivision of the PVN (PaMP), central (CeA) and medial amygdala (MeA) and ventral subiculum of the hippocampus (vSub). Plasma CT levels in animals treated with 6.5 weeks of estrogen were elevated before and 1 h after restraint stress induction. Results indicate that the estrogen chronicity and CMS exposure impacted CT secretion. Neuronal PaMP, CeA, MeA and vSub activity decreased after 4.5 weeks of CMS in all groups. No differences were detected between CMS and non-CMS groups. These data suggest that the HPA central hyporesponsiveness observed in the experimental groups subjected to a longer protocol period was independent to CMS paradigm and estrogen treatment restored partially its activity. These data suggest that additional stressors could be responsible for the observed alterations of the HPA axis.
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Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Sistema Hipófise-Suprarrenal / Estresse Psicológico / Sistema Hipotálamo-Hipofisário Tipo de estudo: Guideline / Prognostic_studies Limite: Animals Idioma: En Revista: Brain Res Ano de publicação: 2019 Tipo de documento: Article País de afiliação: Brasil País de publicação: Holanda
Texto completo
Adicionar na Minha BVS
Imprimir
XML
PubMed Links
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Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Sistema Hipófise-Suprarrenal / Estresse Psicológico / Sistema Hipotálamo-Hipofisário Tipo de estudo: Guideline / Prognostic_studies Limite: Animals Idioma: En Revista: Brain Res Ano de publicação: 2019 Tipo de documento: Article País de afiliação: Brasil País de publicação: Holanda