An LHRH agonist inhibits FSH-induced cyclic AMP accumulation and steroidogenesis in porcine granulosa cells in culture

Abstract

The direct action of a potent LHRH agonist, [D-Ser-(TBU) 6, des-Gly-NH 2 10]LHRH ethylamide was studied in porcine granulosa cells in primary culture. The LHRH agonist inhibits by 30 to 55% the stimulatory effect of FSH on cyclic AMP accumulation up to 9 hours of incubation. In the absence of FSH, a more transient inhibitory effect is observed on cyclic AMP levels. The LHRH agonist inhibits both basal and FSH-induced progesterone secretion. The present data suggest that ovarian LHRH receptors are negatively coupled to adenylate cyclase.