An Intraovarian Inhibitory Action of Estrogen on Angrogen Production In vivo1

Abstract
Subcutaneous administration of estradiol-17β (1 mg) to intact, immature female rats for 3 days significantly decreased ovarian androgen levels from 34 ± 7 pg/mg in oil treated control rats to 13 ± 2 pg/mg ovarian tissue. It inhibited ovarian responsiveness to LH, as measured by ovarian androgen, but not as measured by ovarian progesterone concentrations. In oil treated control animals, LH caused an approximately 5-fold increase in ovarian androgen levels, whereas ovarian androgen levels were not stimulated at all by LH in the estrogen treated rats. This inhibitory effect on ovarian androgen response was also demonstrable after 6 h of estrogen treatment.