Evaluation of aggressive behavior in a perimenopause-animal model induced by 4-vinylcyclohexene diepoxide (VCD) in female rats: role of vasopressin neurons

• Grant number: 15/15831-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2015
• End date: March 31, 2017
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal Investigator: Janete Aparecida Anselmo Franci
• Grantee: Litamara Carolina Dalpogeto
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Perimenopause, a transition period that precedes menopause, is characterized by neuroendocrine, metabolic and behavioral changes. These changes may be result of ovarian failure and consequent reduction of number of follicles, which may lead to the emergence of many symptoms. In this period, women experience episodes of irritability and aggressiveness, which can be related to the hormonal pattern displayed by them, normal or elevated concentrations of estrogens and low levels of progesterone and testosterone. In rodents, 4-vinylcyclohexene diepoxide (VCD) induces a gradual depletion of ovarian follicles, modeling thetransition to menopause in women. Recently we show that female rats treated with VDC express more aggressive behavior than control female rats. In addittion, it is known that vasopressin (AVP) plays an important role in the regulation of the aggressive behavior. The vasopressinergic neurons localized in different nuclei of the hypothalamus, such as the paraventricular nucleus (PVN), bed nucleus of the stria terminalis (BNST) and the vasopressinergic fibers that project to the lateral septum (SL) participate in the neural network involved in the modulation of aggressiveness. Thus, it is possible that during perimenopause functional changes in the vasopressinergic system, which is involved in controlo f aggressive behavior, may contribute to the occurrence of more aggressiveness observed in a previous study. Thus, this project aims to evaluate, by immunohistochemistry, whether this increased aggression observed in the model of perimenopause induced by VCD is accompanied by changes in the activity of vasopressinergic neurons in the PVN and BNST, the density of immunoreactive fibers to AVP in the SL, and if the possible changes in vasopressinergic system might modify the activity of SL neurons.