[Antigonadotropic actions of prolactin. Study of 10 cases of women with hyperprolactinemia]

Abstract

In order to determine the pituitary or ovarian site of the anti-gonadotrophic action of prolactin (PRL), ten women with hyperprolactinaemia were studied in the following way: 1) Repeated estimations of PRL, gonadotrophins (LH and FSH), plasma estradiol and progesterone during six weeks of treatment with bromocriptine. 2) Verification of the effects of estradiol benzoate on LH and FSH levels before and after normalisation of prolactin. 3) Exploration of the ovarian response to the administration of human menopausal gonadotrophin. Without it being possible to exclude any direct effect of prolactin on the ovary, it may be affirmed that the hormone decreases the sensitivity of the gonadotrophic cells to the positive feedback mechanism exerted by plasma estradiol.

PIP: To determine the pituitary or ovarian site of the antigonadotropic action of prolactin (PRL), 10 women with hyperprolactinemia were studied; 1) Repeated estimations of PRL, luteinizing hormone (LH), follicle stimluating hormone (FSH), plasma estradiol, and progesterone during 10 weeks of treatment with bromocriptine. 2) Verification of the effects of estradiol benzoate on LH and FSH levels before and after normalization of prolactin. 3) Exploration of the ovarian response to the administration of human menopausal gonadotropin. Although it is impossible to exclude any direct effect of PRL on the ovary, it may be affirmed that the hormone decreases the sensitivity of the gonadotropic cells to the positive feedback mechanism exerted by plasma estradiol.