Prolactin directly inhibits basal as well as gonadotropin-stimulated secretion of progesterone and 17 beta-estradiol in the human ovary.
An ovarian perifusion technique was used to determine if there is a direct suppressive effect of PRL on human gonadal steroid secretion. Ovarian tissue from nine patients was examined. Ovine PRL (0.1-10 IU/ml) directly suppressed progesterone and 17 beta-estradiol secretion by human ovaries. hCG (1-10 IU/ml) stimulated both progesterone and 17 beta-estradiol secretion. Simultaneous administration of PRL (5-10 IU/ml) suppressed the stimulatory effect of hCG. The ovarian tissue obtained from a hyperprolactinemic patient did not respond to hCG. These results indicate that PRL inhibits both basal and gonadotropin-stimulated ovarian steroid secretion by human ovaries and that this may be one cause of the hypogonadism associated with hyperprolactinemia.
D000328:Adult; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004715:Endometriosis / Q000378:metabolism; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D010048:Ovarian Cysts / Q000378:metabolism; D010053:Ovary / Q000187:drug effects / Q000378:metabolism*; D010911:Pituitary Neoplasms / Q000378:metabolism; D011374:Progesterone / Q000378:metabolism*; D011388:Prolactin / Q000494:pharmacology*
D006063:Chorionic Gonadotropin; D011374:Progesterone; D004958:Estradiol; D011388:Prolactin