Human growth hormone enhances progesterone production by human luteal cells in vitro: evidence of a synergistic effect with human chorionic gonadotropin.

OBJECTIVE To examine the possible direct effect of human growth hormone (hGH) on basal and human chorionic gonadodotropin (hCG)-stimulated progesterone (P) production by cultured human luteal cells. DESIGN Cultures of human luteal cells from early and midluteal phase. SETTING All corpora lutea were obtained from the Obstetrics and Gynecology Department of the Catholic University, a public care center. PATIENTS, PARTICIPANTS Twelve nonpregnant women between 35 and 47 years of age underwent surgery for various nonendocrine disorders such as leiomyomatosis. INTERVENTIONS Corpora lutea were obtained at the time of hysterectomy. MAIN OUTCOME MEASURE Luteal cells were incubated with or without hCG and/or hGH at different concentrations. RESULTS Human growth hormone neither at 250 nor at 500 ng/mL increased basal P production, whereas from 1,000 ng/mL P concentration in media was significantly increased (P less than 0.05). The concomitant treatment with uneffective doses of hCG (6 and 12 ng/mL) and hGH (250 and 500 ng/mL) enhanced P production similarly to that obtained with the highest doses of hGH (1,000 ng/mL or more) or hCG (25 to 50 ng/mL) alone. CONCLUSIONS These results indicate a direct effect of hGH on the luteal steroidogenesis in vitro.