Differential effects of ethanol on luteinizing hormone, follicle stimulating hormone and prolactin secretion in the female rat.

Serum luteinizing hormone (LH), follicle stimulating hormone (FSH) and prolactin (Prl) levels were determined in ovariectomized rats following short-term (3 day) ethanol (ETOH) administration. ETOH was given either as an ETOH-saline solution, or via a liquid diet regimen (Bio-Serve, Inc.). Rats receiving the ETOH-saline solution (3.0 g ETOH/kg) were injected via a permanent gastric cannula every 8 hr for 3 consecutive days, while control animals received injections of saline only. Each animal receiving the liquid diet regimen was provided with 40 ml of the ETOH or the isocaloric control diet ad lib during the lights-off period, followed by 40 ml of the respective diet via the gastric cannula (4 injections of 10 ml each) equally divided over the lights-on period. Additional control animals were cannulated and maintained on Lab Chow and water, but were left untreated. Both groups of ETOH-treated rats had significantly lower serum LH levels with significantly higher Prl levels when compared to values in their respective control animals. By contrast, ETOH failed to alter FSH levels. These data indicate that ETOH can differentially affect LH, FSH, and Prl secretion following short-term ETOH exposure. The dissociation observed between LH and FSH secretion following ETOH supports the hypothesis that there are separate hypothalamic control mechanisms for LH and FSH secretion.