Investigation of the involvement of sex differences in CRFergic neurotransmission of the medial prefrontal cortex and BNST over anxiety and corticosterone levels in mice exposed to social defeat stress.

• Grant number: 24/07023-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: December 01, 2024
• End date: January 31, 2026
• Field of knowledge: Biological Sciences - Pharmacology - Neuropsychopharmacology
• Principal Investigator: Ricardo Luiz Nunes de Souza
• Grantee: Daniel Enrique Gonzalez Escobar
• Host Institution: Faculdade de Ciências Farmacêuticas (FCFAR). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Anxiety is characterized by an emotional response to aversive stimuli, even when they are absent from the immediate environment. Anxiety disorders are globally prevalent, with females exhibiting a higher incidence compared to males, presumably because of physiological, genetic and social factors, such as psychosocial stress. The Chronic Social Defeat Stress model (CSDS) enables research regarding the effects of this kind of stress on behavior as well as the function of brain structures such as the medial pre-frontal cortex (mPFC) and the bed nucleus of the stria terminalis (BNST), with an emphasis on the role of CRF in the performance of anxiety-like behavior and the increase of corticosterone levels on male and female mice. In this study, we aim to investigate the sex differences in CRF neurotransmission and activation patterns of the mPFC and BNST and their impact on anxiety and plasma corticosterone levels in mice subjected to CSDS. Sixty postnatal day (PND) male and female Swiss-Webster mice will undergo the CSDS protocol, followed by behavioral testing using the social interaction test (SIT) and the elevated plus maze (EPM). Prior to EPM testing, animals will receive an intraperitoneal administration of the CRF type 1 receptor antagonist (CP376395).Following EPM testing, subjects will undergo encephalon and blood extraction for the quantification of cFos expression(in mPFC and BNST) and analysis of plasma corticosterone levels , respectively.