This research will provide new information about how hormones specifically control hunger. Decisions about how much to eat are affected by the amount of food previously eaten and the need to engage in other activities. Thus, motivation to eat will be carefully measured in either food-limited or food-unlimited laboratory rodents that will be provided with behavioral options, including the ability to interact with other members of their species. Experiments are designed to determine whether gonadotropin-inhibiting hormone (GnIH) increases the appetite for food, inhibits the reproductive system, or both, and to specify how GnIH orchestrates behavioral priorities. The activation of individual brain cells that secrete GnIH will be measured using immunohistochemistry and a map will be created of the GnIH-cell activation that occurs at the time hunger levels increase and decrease. Drugs that block GnIH binding to its receptors will be used to determine whether GnIH is necessary for food-restriction-induced changes in hunger and the reproductive system. Other experiments will examine whether hormones secreted by the ovary control neural activity in GnIH cells. This project will offer important insights into the high incidence of obesity and eating disorders in women and explore links to the side effects of contraceptive and hormone replacement therapy. This research will have broad impact on the public's understanding of appetite and its interaction with reproduction, fertility, exercise, health, lifestyle, drugs, and prescription hormones. The funding will be used to establish a collaboration with the Kriegsfled laboratory, to team-train graduate and undergraduate students, and to engage in K-12 outreach activities. The award will provide support for the PI's participation, as an NSF ADVANCE chair, in STEM women's seminars and a "writing boot camp". In addition to using traditional publication venues, both PI's will disseminate their work via their webpages and behavioral endocrinology blogs.
