Chronic unpredictable mild stress alters an anxiety-related defensive response, Fos immunoreactivity and hippocampal adult neurogenesis

Autor(es):Mostrar menos -

de Andrade, J. S. ^[1] ; Cespedes, I. C. ^[1] ; Abrao, R. O. ^[1] ; dos Santos, T. B. ^[1] ; Diniz, L. ^[2] ; Britto, L. R. G. ^[2] ; Spadari-Bratfisch, R. C. ^[1] ; Ortolani, D. ^[1] ; Melo-Thomas, L. ^[1] ; da Silvaa, R. C. B. ^[1] ; Viana, M. B. ^[1]

Afiliação do(s) autor(es)

^[1] Fed Univ Sao Paulo UNIFESP, Dept Biosci, Santos, SP - Brazil

^[2] Univ Sao Paulo, Inst Biomed Sci, Dept Physiol & Biophys, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Behavioural Brain Research; v. 250, p. 81-90, AUG 1 2013.
• Citações Web of Science: 28

Resumo

Previous results show that elevated T-maze (ETM) avoidance responses are facilitated by acute restraint. Escape, on the other hand, was unaltered. To examine if the magnitude of the stressor is an important factor influencing these results, we investigated the effects of unpredictable chronic mild stress (UCMS) on ETM avoidance and escape measurements. Analysis of Fos protein immunoreactivity (Fos-ir) was used to map areas activated by stress exposure in response to ETM avoidance and escape performance. Additionally, the effects of the UCMS protocol on the number of cells expressing the marker of migrating neuroblasts doublecortin (DCX) in the hippocampus were investigated. Corticosterone serum levels were also measured. Results showed that UCMS facilitates ETM avoidance, not altering escape. In unstressed animals, avoidance performance increases Fos-ir in the cingulate cortex, hippocampus (dentate gyrus) and basomedial amygdala, and escape increases Fos-ir in the dorsolateral periaqueductal gray and locus ceruleus. In stressed animals submitted to ETM avoidance, increases in Fos-ir were observed in the cingulate cortex, ventrolateral septum, hippocampus, hypothalamus, amygdala, dorsal and median raphe nuclei. In stressed animals submitted to ETM escape, increases in Fos-ir were observed in the cingulate cortex, periaqueductal gray and locus ceruleus. Also, UCMS exposure decreased the number of DCX-positive cells in the dorsal and ventral hippocampus and increased corticosterone serum levels. These data suggest that the anxiogenic effects of UCMS are related to the activation of specific neurobiological circuits that modulate anxiety and confirm that this stress protocol activates the hypothalamus-pituitary-adrenal axis and decreases hippocampal adult neurogenesis. (C) 2013 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 11/17471-0 - Efeitos do estresse agudo e crônico sobre respostas comportamentais de defesa
• Beneficiário: Milena de Barros Viana
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 11/01409-4 - Estimulação elétrica e registro da atividade neural do colículo inferior durante a catalepsia induzida pelo haloperidol: estudo comportamental e eletrofisiológico
• Beneficiário: Liana Melo-Thomas
• Modalidade de apoio: Auxílio à Pesquisa - Regular