Alcohol effects on luteinizing hormone-releasing hormone stimulated luteinizing hormone and follicle-stimulating hormone in ovariectomized female rhesus monkeys.

The effects of acute alcohol administration on anterior pituitary function were studied in five ovariectomized female rhesus monkeys. Integrated plasma samples were collected for 80 min before and 120 min after nasogastric intubation of alcohol (2.5 or 3.5 g/kg) or isocaloric sucrose control solution. Then synthetic luteinizing hormone-releasing hormone (LHRH; 100 micrograms/i.v.) was administered and plasma samples were collected for an additional 180 min. After sucrose control administration, LHRH stimulated a significant increase in luteinizing hormone (LH) within 30 min (P less than .001) and follicle-stimulating hormone (FSH) within 60 min (P less than .01). After alcohol administration, LHRH stimulated LH and FSH also increased significantly (P less than .01) when blood alcohol levels averaged 242 (+/- 26) and 296 (+/- 20) mg/dl. Moreover, there was an alcohol dose-dependent increase in LHRH-stimulated LH (P less than .01, .001) in comparison to control conditions, even though prealcohol and presucrose LH levels were equivalent. LHRH-stimulated FSH was also higher after 3.5 g/kg of alcohol than after 2.5 g/kg of alcohol and sucrose control administration (P less than .001) but base-line FSH levels before 3.5 g/kg of alcohol were also higher than control (P less than .05) or 2.5 g/kg of alcohol (P less than .001). An alcohol related enhancement of LHRH-stimulated LH without concomitant suppression of FSH in ovariectomized females contrasts with data reported previously in normally cycling females studied under identical conditions. The absence of ovarian steroid and/or ovarian peptide negative feedback in ovariectomized females may have permitted the synergistic effect of alcohol and LHRH on LH.