Reproductive experience makes a mother to be more resistant to pain? Molecular, physiological and behavioral aspects of nociception in female rats

• Grant number: 11/16109-6
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2012
• End date: February 28, 2014
• Field of knowledge: Biological Sciences - Pharmacology - Neuropsychopharmacology
• Principal Investigator: Elizabeth Teodorov
• Grantee: Elizabeth Teodorov
• Host Institution: Centro de Matemática, Computação e Cognição (CMCC). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil

Abstract

It is the popular belief that a mother undergoes any sacrifice to ensure the survival of his son, whether human or animal species. We also know that motherhood makes the mother more aggressive with strangers and their pain threshold seems to reach very high levels, since it can submit to cold, heat and intense hunger since your child anything to suffer. Thus it is assumed that the woman / female has an imput to be maternal, particularly when there is the presence of the child / offspring and that there is an endogenous analgesic mechanism activated when the female is in this situation. The emergence and maintenance of so-called maternal behavior (CM) are controlled by the interaction of environmental, biochemical, hormonal and neural. Analyzing brain of rodents districts involved in the modulation of the CM as the medial preoptic area (APOM) also came to the periaqueductal gray (PAG), an important region involved in reproduction, food intake, nociception and aggressive due to the high density of opioid receptors. There are few works that focus on the role and molecular biology of the subtypes of opioid receptors (known as one, kappa and delta), and these could modulate nociception in lactating rats, starting from the principle that a parent has a higher threshold for pain and this could increase with multiparity. This project aims to investigate whether rats nulliparous, primiparous or multiparous have molecular alterations in the expression of each subtype of opioid receptor in the PAG, hypothalamus and striatum, as well as sensitivity to pain. The hypothesis for the study is that the expression of genes that encode for these receptors in these brain regions and their protein products could be modulated by maternal experience, with possible implications in nociceptive processes essential to the survival of the species. (AU)