Gonadotrophs Following Removal of the Ovaries: a Fine Structural Study of Human Pituitary Glands

The fine structure of gonadotrophs has been investigated in surgically removed pituitary glands of 12 women who because of disseminated breast cancer, underwent bilateral ovariectomy at various periods before hypophysectomy. Compared with the adenohypophyses of 3 non-ovariectomized female subjects with diabetes mellitus, electron microscopy revealed that two cell types were affected by gonadectomy. These cell types corresponded to those which were regarded as FSH gonadotrophs and LH gonadotrophs in previous studies. In addition in the adenohypophyses stimulated by removal of the ovaries, intermediary cell types began to appear suggesting a transformation of LH gonadotrophs to FSH gonadotrophs. The most conspicuous change following gonadectomy was the formation of castration cells. These cells arose from FSH gonadotrophs and exhibited ultrastructural features interpreted as representing the morphologic manifestations of sustained hypersecretion of gonadotrophins. It seemed that castration cells have a limited life span and in their advanced stages of development they show ultrastructural signs indicative of irreversible involution.