Effect of Hypophysectomy and Pretreatment on Uptake and Retention of Estradiol by the Ovary

Immature female rats were used after hypophysectomy to study the characteristics of uptake and retention of 3H-estradiol-17β by the ovary. The concentration of radioactivity in the ovary increased progressively up to 3 days following hypophysectomy. In another study uptake and retention of 3Hestradiol was studied at 2, 4 and 8 hr following a single sc injection (.1 μg/100 g body wt). The ovaries of hypophysectomized rats took up and retained highest amount of radioactivity. The results demonstrate the ability of the ovary to incorporate exogenous estrogen in the absence of endogenous estrogen. Evidence also indicates that the ovaries of immature rats are capable of secreting estrogen.