[Effect of the dose of estradiol and long-term administration of the hormone on the proliferative activity of the epithelium of the cavity, glandular epithelium and stroma of the white rat uterus].

The duration of S-sphase of the cell cycle in uterine epithelial and stroma tissues of ovariectomised rats, treated with two doses of estradiol-17 beta for 4 days, was estimated by the double labeling technique using H3 -and C14-thymidine. Estrogen treatment induced cyclical changes of S-phase duration in the uterine cell compartments, with maximal values at 72 and 24 hours for 1mcg and 1 mg of estradiol. resp. The high dose of estradiol induced five-fold reduction of the mitotic and labeling indices in luminal epithelium in contrast to the effect of the low dose. In the rat glandular epithelium and stroma cells mitotic and labeling indices are not influenced by eith of the estrogen dosis.