Twelve-hour pair housing attenuates stress-induced hyperthermia in response to conditioned stimulus

Abstract

The hypothalamic gonadotropin-releasing hormone (GnRH) pulse generator regulates intermittent GnRH discharge into the pituitary portal circulation, and thereby modulates the pattern of pulsatile secretion of luteinizing hormone (LH). Various internal and external factors first modify the GnRH pulse generator activity, which then alters the pulsatile pattern of gonadotrophin secretion, and eventually influence reproductive function. We have successfully recorded characteristic increases in neuronal activity associated with pulsatile LH secretion from the ovariectomized and cycling female goat by means of a multiple unit activity (MUA) recording technique. The unitary relationship between periodic increases in MUA volleys and LH pulses is well maintained under a variety of experimental conditions, providing evidence that these MUA volleys are the consequence of GnRH pulse generator activity. A procedure that has permitted long-term recording of electrophysiological manifestation of the GnRH pulse generator activity and its research application are described.