[Effect of estradiol on the synthesis of DNA in the female rat liver].

The effect of estradiol on DNA synthesis in hepatocytes was investigated for a study of the functional importance and mechanism of action of sex steroids in the liver. After administration of 17, beta-estradiol dipropionate at a dose of 20 micrograms per 100 g of body mass to ovariectomized albino female rats for 11 days the kinetics of incorporation of 3H-thymidine triphosphate in liver cell nuclei and chromatin was determined. A stimulating effect of the hormone on the tracer incorporation in the nuclei and chromatin was established. A similar tendency was noted in immature female rats. The tracer incorporation depends on the cytosol presence in the system. The rate of incorporation has been shown to increase under the influence of the liver cytosol of intact rats. In can be assumed that estradiol is involved in the regulation of liver DNA synthesis raising matrix activity and modulating cytosol factor activity.