Study of the involvement of CRFergic neurotransmission in the bed nucleus of the stria terminalis in autonomic response to acute restraint stress in rats

• Grant number: 13/00898-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: May 01, 2013
• End date: April 30, 2015
• Field of knowledge: Biological Sciences - Pharmacology - Neuropsychopharmacology
• Principal Investigator: Carlos Cesar Crestani
• Grantee: Leandro Augusto de Oliveira
• Host Institution: Faculdade de Ciências Farmacêuticas (FCFAR). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

The maintenance of homeostasis during stress is mediated by the coordinated activation of autonomic and neuroendocrine systems. The autonomic adjustments during stress are characterized by cardiovascular changes that include: increase in blood pressure and heart rate, reduction in visceral and cutaneous blood flow and changes on baroreflex activity. Although the importance of autonomic responses during threat situations, the neurobiological mechanisms involved in these responses are poorly understood. The physiological and behavioral responses during stress are mediated by limbic structures in the central nervous system. The bed nucleus of the stria terminalis (BNST) is a limbic structures localized in the rostral prosencephalon. It has been demonstrated an involvement of the BNST in autonomic, neuroendocrine and behavioral responses to aversive stimuli. However, the local neurochemical mechanisms in the BNST involved in control of responses to stress are poorly understood. The release of corticotropin-releasing factor (CRF) in limbic structures during aversive threat is an important mechanism associated with physiological and behavioral responses to stress. In fact, numerous studies demonstrated a role of BNST CRFergic neurotransmission in behavioral responses to stress. However, evidence regarding a possible involvement of this neurochemical mechanism of the BNST in cardiovascular responses to stress is limited. Therefore, our proposal in the present study is to test the hypothesis that the BNST CRFergic neurotransmission is involved in autonomic responses to acute restraint stress in rats. To test this hypothesis, our aim is to investigate the effect of local bilateral microinjection into the BNST of agonists and antagonists of the CRF1 and CRF2 receptors in blood pressure and heart rate increase as well as in reduction of tail cutaneous temperature induced by acute restraint stress in rats. (AU)