Effect of RNA from estradiol-treated immature rats on protein synthesis in immature uteri.

Abstract

The role and organ specificity of RNA in mediating estradiol-induced growth of the uterus of immature rats was studied. RNA preparations from uteri and other organs of estradiol-treated immature rats were injected into one uterine horn, the contralateral horn serving as control. The time course of the increase in the incorporation of amino acids into uterine proteins after the application of estradiolinduced uterine RNA was similar to that after the systemic application of estradiol, reaching a peak after 24 hr. RNA preparations from kidney, adrenals, lungs, skeletal muscle and thymus had no effect on protein synthesis in uteri. RNA extracted from the liver of estradiol-induced immature rats resembled uterine RNA in increasing uterine protein synthesis. The results suggest that uterine RNA mediates the estradiolinduced protein synthesis in the uterus. The unexpected effect of liver RNA in the uterus is discussed in view of the role of the liver in the metabolism of estrogens. (Endocrinology88: 279, 1971)