GLYCOPROTEIN HORMONES AND THEIR COMMON ALPHA-SUBUNIT STIMULATE PROLACTIN PRODUCTION BY EXPLANT CULTURES OF HUMAN LEIOMYOMA AND MYOMETRIUM

OBJECTIVE: The purpose of this study was to examine the effect of the gonadotropins luteinizing hormone, follicle-stimulating hormone, and h uman chorionic gonadotropin on prolactin production by human leiomyoma s and myometrium. A secondary goal was to explore the effect of thyroi d-stimulating hormone and the alpha-subunit common to all these glycop roteins in the same system. STUDY DESIGN: Explant cultures were establ ished, and harvested medium was assayed for total protein and prolacti n. Dose-response studies were performed with follicle-stimulating horm one, luteinizing hormone, and human chorionic gonadotropin. A second s et of studies was conducted with a single dose of human chorionic gona dotropin, thyroid-stimulating hormone, and alpha-subunit. RESULTS: Gon adotropins, thyroid-stimulating hormone, and alpha-subunit all stimula ted prolactin production in both leiomyoma and myometrium. Prolactin p roduction was significantly higher in leiomyoma than in myometrium. A positive effect of time, dose, and gonadotropin treatment on prolactin production was seen in each tissue. There was no treatment effect on total protein secretion. CONCLUSIONS: All four glycoprotein hormones a nd their common alpha-subunit stimulate prolactin production. This app ears to be a specific effect.