THE LHRH PULSE-GENERATOR - A MEDIOBASAL HYPOTHALAMIC LOCATION

The location and mechanism of LHRH pulse generator are discussed based on our series of experiments. Suckling stimulus is a novel stimulus t hat inhibits LH pulses without any cooperation from ovarian steroids, unlike other stimuli such as stress, photoperiod etc. It is directly i nvolved in suppressing the activity of the LHRH pulse generator. The i nformation from teats suckled by pups or babies is conveyed dorsally t o the mediobasal hypothalamus (MBH), where the LHRH pulse generator ma y be located. Experiments using various types of deafferentation and f etal brain tissue transplantation confirmed that the LHRH pulse genera tor is located in the MBH and suggested that LHRH pulse generator cons ists of nonLHRH neurons. Endogenous excitatory amino acid is one of th e possible neurotransmitters that regulate LHRH release at the nerve t erminal in ME.