Angiotensin II (AII) modulation of steroidogenesis by luteinized granulosa cells in vitro.

PURPOSE: The purpose of the present study was to evaluate the effect of angiotensin II and its inhibitor, saralasin, on steroid production by luteinized human granulosa cells in vitro. Granulosa cells were obtained from follicular fluid aspirations from human in vitro fertilization. Cultures were established in supplemented Ham's F-10 medium. Human chorionic gonadotropin and angiotensin II were added to culture media and the effect on steroid production was measured.

RESULTS

Human chorionic gonadotropin alone stimulated production of progesterone, estradiol, and testosterone. The addition of angiotensin II resulted in a dose-dependent increase in progesterone production (428% increase compared to baseline). No effect was seen on estradiol or testosterone. However, a large increase (700%) in estradiol was seen with the addition of the competitive inhibitor of angiotensin II, saralasin.

CONCLUSION

We conclude that angiotensin II modulates progesterone production by human luteinized granulosa cells in vitro. The observed enhancement of estradiol production by angiotensin blockade suggests a tonic inhibition of estradiol secretion by endogenous angiotensin II.