Effect of estradiol on RNA synthesis and nuclear protein phosphorylation in rat liver

Experiments were made to study the effect of 17, beta-estradiol on the RNA synthesis and nuclear protein phosphorylation in the liver of sexually mature female albino rats: sham-operated, ovariectomized and hormone-treated after the ovariectomy (20 micrograms estradioldipropionate/100 g body mass). The rate of RNA synthesis is determined in vivo by the 3H-uridine incorporation in the acid-insoluble fraction, whereas the nuclear protein phosphorylation is determined in vitro by the incorporation of gamma-32 P-ATP in isolated cell nuclei. Increased RNA synthesis is found to occur under the effect of the hormone, which corresponds to the hormone's effect on the uterine cells. The hormone stimulates the nuclear protein phosphorylation--an effect which could be associated with the gene expression.