Meeting Abstract
29.6 Monday, Jan. 5 A springtime KiSS?: Uncovering a role for the neuropeptide kisspeptin in seasonal reproduction GREIVES, Timothy J*; KRIEGSFELD, Lance J; DEMAS, Gregory E; Department of Biology and Center for Integrative Study of Animal Behavior, Indiana University, Bloomington, 47405, USA; Department of Psychology and Helen Wills Neuroscience Institute, University of California, Berkeley, 94720, USA. tjgreive@indiana.edu
Most non-tropical animals exhibit seasonal bouts of reproduction, and photoperiod acts as the main environmental cue regulating the timing of breeding. The integration of photoperiod cues ensures offspring are born during favorable environmental conditions. The precise mechanisms by which photoperiodic information are integrated to directly regulate the reproductive neuroendocrine axis has, however, remained less well specified. The neuropeptide kisspeptin has recently been identified as a potent positive regulator of reproductive function and is associated with the onset of puberty in laboratory mammals and humans. We investigated the role of kisspeptin in regulating seasonal changes in reproduction in the photoperiodic Siberian hamsters (Phodopus sungorus). The reproductive neuroendocrine axis of Siberian hamsters is tightly regulated by changes in photoperiod; hamsters held in summer-like long-days maintain fully functional gonads, while animals held winter-like short-days regress their gonads and are reproductively quiescent. To begin to uncover the role of kisspeptin in seasonal reproduction, hamsters were subjected to hormonal and photoperiod manipulations; hamsters were housed either in summer-like long days (L:D 16:8) or winter-like short days (L:D 8:16). The effects of hormonal and photoperiod manipulation on the kisspeptin system and the effects of kisspeptin on the reproductive neuroendocrine axis in reproductive and non-reproductive hamsters will be presented. Further, the potential role of kisspeptin as a key modulator of seasonal reproductive activity will be discussed.
