[Ultrastructural localization of estradiol and moxestrol in the gonadotropic cells of rat by immunocytology after cryo-ultramicrotomy: evidence for hormonal specificity (author's transl)].

Estradiol (E2) was specifically localized by immunocytochemistry in the cytoplasm and in the nucleus of the gonadotropic cells. The immunocytochemical reaction was not observed after injection of moxestrol, but it was not modified by injection of testosterone, progesterone, or dexamethasone. These data suggest that E2 might be bound to a high-affinity binding-site which could also have a hormonal specificity.