"Role of estradiol in thermoregulatory behavior and hyperalgesia in ovariectomized rats"

• Grant number: 17/21796-9
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: February 18, 2018
• End date: October 17, 2018
• Field of knowledge: Biological Sciences - Physiology - General Physiology
• Principal Investigator: Luiz Guilherme de Siqueira Branco
• Grantee: Bruna Maitan Santos
• Supervisor: Andrej Romanovsky
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Institution abroad: St. Joseph's Hospital and Medical Center, United States
• Associated to the scholarship: 16/09364-3 - Role of endogenous preoptic hydrogen sulfide modulating LPS tolerance., BP.DR

Abstract

Sex hormones, such as estradiol, play an important role in body temperature regulation and pain sensation. Low estradiol concentrations, often seen in menopausal women, are associated with the occurrence of hot flushes, which are characterized by an intense sensation of heat, followed by profuse sweating and an increase in blood flow to the skin, which leads to reddening of the face and upper torso and an increase in skin temperature. Moreover, it is commonly observed that climacteric women that experience hot flushes try to cool themselves by using air conditioners, by opening windows and undressing, and most of them report an increase in pain sensitivity (called hyperalgesia). However, the mechanisms associated with hyperalgesia and the behaviors employed by menopausal women to cool the body (called behavioral thermoregulation) have been poorly investigated. Our hypothesis is that estradiol withdraw is associated with the thermoregulatory behavior and hyperalgesia observed in menopusal women. We expected that female rats that have had their ovaries removed (ovariectomized rats), and, therefore, present low estradiol concentrations, would prefer to stay at lower ambient temperatures, avoid warmer temperatures and present hyperalgesia, and that estradiol replacement will reverse these effetcs of ovariectomy in the behavioral thermoregulation and pain sensation.