Selective inhibition of luteinizing hormone action by ethanol in cultured human granulosa cells

To extend further our previous observations on the inhibition of luteinizing hormone (LH)-induced increases in steroid secretion by ethanol (EtOH) (Alcohol. Clin. Exp. Res. 14:522-527, 1990), cultured human granulosa cells were pretreated with several EtOH concentrations (0-100 mM), and cells were stimulated with human LH (25 ng/ml) or human follicle stimulating hormone (FSH) (100 ng/ml) and the secretion of 17-beta-estradiol (E2) and progesterone (P) was measured. EtOH significantly increased basal E2 secretion in a dose-related manner (0-20 mM); however, in the same concentration range EtOH did not produce consistent changes in FSH-stimulated E2 secretion. In contrast, EtOH decreased LH-stimulated E2 secretion between 0-20 mM such that at 20 mM EtOH, the positive effect of LH was abolished. EtOH increased P secretion by 40% at 20 mM and at 100 mM, there was a 100% increase. The FSH-stimulated P secretion was not consistently changed by EtOH, whereas LH-stimulated P secretion was decreased in a dose-dependent manner. LH/human chorionic gonadotropin (hCG) receptors in cells exposed to EtOH showed a 15% (p < 0.01) and a 47% decrease at 20 mM and 50 mM EtOH, respectively. At 50 mM EtOH, there was a decrease in LH/hCG receptor number from 2900/cell to 1670/cell, without a change in receptor affinity for hCG and 50 mM EtOH decreased LH/hCG receptors in intact granulosa cells in a time-dependent manner. These results indicate that the selective effects of EtOH on LH action in human granulosa cells may be mediated in part by an action on LH/hCG receptors.