Steroidogenesis in immature chicken ovary. Hormonal stimulation of adenylyl cyclase system by luteinizing hormone and beta-adrenergic agonists.

The presence of a hormonally responsive adenylyl cyclase in the immature chicken ovary was investigated. We found that there was a highly significant difference (P < 0.05) between basal and LH and catecholamine activatable activities. In addition, the basal activity was stimulated by NaF, forskolin and the non-hydrolyzable GTP analogue guanosine-5'-(beta,gamma-imido)-triphosphate (GMP-P(NH)P. The action of catecholamines on cyclic AMP and progesterone production was also investigated and compared to that of LH. The stimulatory effect of isoproterenol on cyclic AMP and progesterone production was significantly higher (P < 0.05) than that of LH. The beta-adrenergic antagonist propranolol caused complete inhibition of the stimulatory action of catecholamines. Progesterone accumulation induced by LH or isoproterenol was synergistically augmented by the simultaneous presence of both inducers.