Phorbol ester stimulates human granulosa-luteal cell cyclic adenosine 3', 5'-monophosphate and progesterone production.

Human granulosa-luteal cell production of cyclic adenosine 3', 5'-monophosphate (cAMP) and progesterone (P) were studied in response to 12-O-tetradecanoyl-phorbol-13-acetate (TPA). TPA specifically increased cAMP synthesis in a dose-dependent manner. A 7-fold increase occurred at a TPA concentration of 1 ng/ml. Time-course studies indicated that the increase in accumulation of cAMP into culture media became detectable at 4 h and continued up to 72 h. TPA also enhanced P synthesis, but the increase was statistically significant only at 72 h. Indomethacin prevented TPA-stimulated cAMP and P production. The results suggest that TPA stimulates granulosa-luteal cell cAMP and P production, and that the action of TPA is mediated by the increase in prostaglandin synthesis.