Chronic recording of electrophysiological manifestation of the hypothalamic gonadotropin-releasing hormone pulse generator activity in the goat.

A characteristic increase in multiple-unit activity (MUA volley) synchronized with the pulsatile secretion of luteinizing hormone (LH) by the pituitary gland was recorded from electrodes chronically implanted in the medial basal hypothalamus of ovariectomized goats. The MUA volley always preceded the LH pulse, and the temporal correlation was consistent even when the pulse frequency was altered with an anesthetic or exogenous steroids. The electrophysiological manifestation of the hypothalamic 'pulse generator' governing the secretion of gonadotropin-releasing hormone was thus demonstrated in the ruminant.