Effect of ethanol on uterotropic action of estrogens

Female rats aging 3 months at the beginning of experiments received 5 or 15% ethanol and then were subjected to bilateral ovariectomy 2 weeks before end of the experiment. During the last 11 days they were daily injected intramuscularly with 2 μg estradiol. Drinking of 5% ethanol combined with injections of estrogens induced DNA damage in the uterus detected by comet assay and abolished induction of progesterone receptors, changes in peroxidase activity, proliferation index, endometrium thickness, and other indices reflecting the hormonal effect of estradiol on the uterus. Drinking of 15% ethanol was accompanied by an increase in DNA-damaging effects of estrogens and a decrease in their hormonal uterotropic effects. It is concluded that unlike tobacco smoking, drinking of moderate ethanol concentrations modifies primarily genotoxic, but not the hormonal effect of estrogens.