Alteration of Rat Uterine Alkaline Ribonuclease and Ribonuclease Inhibitor Activity Following the Administration of Estradiol

Summary

Rat uterine active and total alkaline RNase and inhibitor activity were measured following 2-6 hr estradiol (E₂) treatment of ovariectomized animals. Although active RNase data vary during the treatment period, a significant decrease below control level was observed 6 hrs after hormone administration. Simultaneously, E₂ stimulated an increase in uterine RNase inhibitor activity of 18-50 percent. Hormonal increased uterine RNase inhibitor activity was blocked by treatment with cycloheximide. E₂ stimulated RNase inhibitor activity may act in conjunction with a slow reduction in total RNase activity to stabilize the various species of uterine cytoplasmic RNA necessary for the anabolic activity of the hormone.

Key-Words:

Estradiol - Uterus (Rat) - Ribonuclease - RNase Inhibitor