Abstract
Factors that may affect the estrogenization of postmenopausal women are important because estrogen levels may modulate the risk of osteoporosis and cardiovascular disease in postmenopausal women. Ethanol, a potential estrogenization factor, has received scant attention, particularly in postmenopausal women who are moderate users of alcoholic beverages. Because as many as 22.6% of postmenopausal women are reported to have had a bilateral oophorectomy, mature oophorectomizd rats were used as a model. Low to moderate ethanol consumption was approximated by administering graded doses of ethanol in drinking water (0, 1.8, 3.7 or 5.5% ethanol, v/v) to 90 oophorectomized rats for 4 or 10 weeks. In rats exposed for 4 weeks, neither estradiol levels nor uterus weight differed among the four groups. In contrast, among rats exosed to 10 weeks, there was a significant positive correlation between ethanol dose and both uterus weight and estradiol; analysis of variance demonstrated that inclusion of the data obtained from rats receiving the 5.5% ethanol dose accounted for the significance of these associations. Based on these findings, it is suggested that, at least in oophorectomized rats, prolonged exposure to moderate ethanol doses is required to induce sufficient aromatization of androgens to produce detectable changes in plasma estradiol or in uterus weight. Further studies will be required to determine whether low or moderate alcoholic beverage use by postmenopausal women may result in biologically relevant increases in serum estradiol.