INCREASED ACCUMULATION OF ESTROGEN RECEPTORS IN PITUITARY NUCLEI OF DANAZOL TREATED RATS

Orally administered danazol decreased the concentration of parenterally administered [3H]-estradiol in pituitary and hypothalamus, but not in cerebral cortex, relative to plasma levels of labeled hormone in adult, ovariectomized rats. Similarly, danazol increased the amounts of estradiol receptors in pituitary nuclei of these animals. These findings are consistent with the concept that danazol acts at the level of the pituitary and (probably) the hypothalamus in rats to inhibit the production and/or release of gonadotropins.