Effects of Radiation on the Mitotic Rate in the Uterine and Vaginal Epithelia in Ovariectomized Mice Treated with Estradiol

抄録

Mitotic figures in both the vaginal and uterine epithelia in mice disappeared almost completely within one month after ovariectomy. Estradiol injection resulted in a marked rise in the mitotic rate in the epithelia of such ovariectomized mice within 30 hours. Irradiation with 500R of X-rays one hour after estradiol injection was followed by a marked drop in the mitotic activity in both the epithelia 30 hours later. X-irradiation at 3, 6 and 9 hours after estradiol injection gave rise to decreases in the mitotic rate to approximately the same degree in the vaginal epithelium. By contrast, the mitotic rates in the uterine epithelium varied significantly according to the length of the interval between estradiol administration and irradiation.