to investigate the cellular mechanisms involved , levels of total cytoplasmic and nuclear estrogen receptors and cytoplasmic progestin receptors in the hypothalamus-preoptic area ( hpoa ) , pituitary , and uterus were measured by [ 3h ] e2 or [ 3h ] r5020 ( 3h-labeled 17,21-dimethyl-19-nor-4,9-pregnadiene-3,20-dione ) exchange assays at various times after the administration of e2 and /or nafoxidine .
C0007634
cellular
C0010834
cytoplasmic