Neuroanatomical projections and sites regulating anxiety in lactating rats

• Grant number: 12/07008-4
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: August 01, 2012
• End date: March 31, 2013
• Field of knowledge: Biological Sciences - Morphology - Anatomy
• Principal Investigator: Luciano Freitas Felicio
• Grantee: Aline de Mello Cruz
• Supervisor: Joseph S. Lonstein
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: Michigan State University (MSU), United States

Abstract

The interaction between mother and child that occurs in the postpartum period is critical to the physical, cognitive and psychological development of the children. This interaction depends on several factors, and the mother's positive emotional state is one of the most important for the psychological development of children. However, many mothers in the postpartum period present emotional instability, and anxiety is often involved. Several mechanisms may be involved in the context of maternal anxiety, such as neuroendocrine, socioeconomic, affective / emotional factors. The pathways involved in maternal anxiety have not been elucidated yet. The bed nucleus of the stria terminalis (BST) is a heterogeneous structure that has been widely associated with the control of certain emotion-related behaviors in mammals, including humans and nonhuman primates. Previous work done with rats show that the BST is involved in the production of anxiety responses. We propose to investigate vBST neurochemistry and projections for the three sites (central amygdaloid nucleus - CEAM, suppramamillar nucleus - SUM and caudal portion of the ventral periaqueductal gray - cPAGv), which receive dense projections vBST and may be responsible for generating anxiety. The hypothesis is that the decrease in anxiety in the postpartum period requires the removal of these sites and input from the vBST is involved in this process. Iontophoretically will apply the retrograde tracer Fluorogold in the nuclei CEAM, SUM or cPAGv in lactating rats. Although we use the technique of immunohistochemistry to visualize the expression of c-Fos in cells of the mother rats vBST after being exposed to the test of the elevated plus maze, which is an important tool to assess behaviors related to anxiety in laboratory animals. It could provides important insights through the mechanisms by which vBST may influence postpartum anxiety. (AU)