Evidence for the involvement of an energy-dependent process in gonadotropin-releasing hormone-stimulated luteinizing hormone release by rat anterior pituitary.

The involvement of an energy-dependent process in gonadotropin-releasing hormone-(GnRH) stimulated LH release in the anterior pituitary has been examined. Inhibitors of both glycolysis and oxidative phosphorylation inhibited stimulation by GnRH of LH release in a time- and dose-dependent manner. Iodoacetate and 2-deoxyglucose inhibited GnRH-stimulated LH release, and this inhibition was not overcome by the addition of pyruvate. Similarly carbonyl cyanide m-chlorophenylhydrazine, an uncoupler of oxidative phosphorylation, and sodium azide, an inhibitor of electron transport, decreased ATP levels, enhanced lactate accumulation, and inhibited GnRHstimulated LH release. These studies demonstrate that inhibition of glycolysis and oxidative phosphorylation with metabolic inhibitors lead to inhibition of GnRH-stimulated LH release. Based on these results, it is postulated that GnRH-stimulated LH release is dependent on an energy-dependent process.