Effect of clomiphene on the uptake of estradiol by the anterior hypothalamus and hypophysis.

Abstract

The administration of clomiphene caused a marked depression in the uptake of tritiated estradiol by the anterior hypophysis and a smaller depression of estrogen uptake by the anterior hypothalamus in adult ovariectomized rats. The minimal effective doses were 0.1 mg/kg/day for 4 days or 1 mg/kg in a single injection. The degree of depression was a function of the dose in both cases. In contrast, clomiphene was without effect on the uptake of estradiol by the posterior hypophysis, the cerebrum, the cerebellum, or the middle and posterior hypothalamus. These results suggest that clomiphene binds or occupies the estradiol-binding “receptors” in the anterior hypophysis and the anterior hypothalamus. (Endocrinology82: 1049, 1968)