Effect of progesterone upon adenylate cyclase activity and cAMP levels on brain areas.

Changes induced by progesterone on adenylate cyclase activity and cAMP levels were determined in brain areas involved in the integration of sexual behavior in ovariectomized estradiol benzoate primed rats. Adenylate cyclase and cAMP concentrations were assayed in: preoptic area, ventromedial hypothalamus and cerebral cortex. Our results show a significant increase in both enzyme activity and cAMP levels at 2 and 4 hours after progesterone administration in all brain areas studied. These data suggest that the facilitatory effect of progesterone on sexual behavior involves an activating mechanism of this steroid upon the adenylate cyclase enzyme which results in an intraneuronal cAMP enhancement.