Poster Presentation The International Congress of Neuroendocrinology 2014

Estrous cycle oscillations in Syrian hamster ingestive and sex behavior are amplified by cold ambient temperature or exercise (#318)

Noah A Benton 1 , Amir Abdulhay 1 , Jill E Schneider 1
  1. Lehigh University, Bethlehem, PA, United States
We previously found that estrous cycle oscillations in food hoarding and sexual motivation are masked in females housed in isolation at 22ÂșC with unlimited food. In these females, food hoarding was low and sexual motivation high throughout the four-day estrous cycle, whereas, in food-limited females, high levels of sexual motivation were restricted to the periovulatory day, and food hoarding was elevated on the nonestrous days. To determine whether cold ambient temperature has the same effects, groups of hamsters were fed ad libitum while they were housed at either 5oC (cold-housed) or 22oC (warm-housed) and tested for sex and ingestive behavior for 90 min on each day of the estrous cycle. Estrous cycle oscillations in food hoarding (but not food intake) were amplified in cold-housed females. Similar to cold-housed females, a group of warm-housed females provided with access to running wheels also showed high levels of sexual motivation restricted to the periovulatory day. Unlike cold-housed females, however, those warm-housed with running wheels showed low levels of food hoarding and significantly elevated levels of food intake. Food limitation, cold housing, and access to wheels had no significant effect on plasma estradiol or progesterone concentrations, but significantly decreased gonadal white adipose tissue pad weight and plasma leptin concentrations. Behavioral responsiveness to low gonadal steroid concentrations is increased by decreased energy intake, or increased energy expenditure on thermogenesis or exercise. Funded by NSF grant IOS-1257876.