Modification of the uterotropic effect produced by estrogens in aging rats.

We studied the influence of various methods for correction of age-related changes (administration of N-acetyl-L-cysteine, vitamins C and E, melatonin, and carnosine and swimming training) on the realization of estrogens effects in ovariectomized rats. The proliferation index in the endometrium decreased in 12-14-month-old control animals. The weight of the uterus, percentage of "comets", and average length of their tail in estradiol-treated rats far surpassed the corresponding parameters in control animals. Administration of melatonin and N-acetyl-L-cysteine and swimming training corrected these genotoxic abnormalities. Our results indicate that aging induces incomplete variant of the phenomenon for switching of estrogen's effects (increase in the severity of genotoxic damage without facilitation of the hormonal effect). These methods for correction of age-related changes have not only common, but also distinguishing characteristics compared to correction of changed induced by drinking of ethanol in various concentrations, whole body gamma-irradiation, and exposure to tobacco smoke.