Effect of Pregnancy and Hormones on the Activity of Aspartate Transcarbamylase and the Level of Nucleic Acids in the Mammary Gland of the Rat1

Abstract

It is well established that pregnancy or the injection of certain hormones results in greatly increased levels of nucleic acids in the mammary gland of the rat. The present study involves the reinvestigation of the levels of nucleic acids in mammary tissue in pregnancy and lactation as well as in hormonally induced growth of the gland in an attempt to correlate the rise in the level of nucleic acids to the activity of aspartate transcarbamylase. A definite chronological correlation exists between enzymatic activity and the accumulation of RNA in mammary tissue in both normal pregnancy and hormonally induced growth. We interpret the results as indicating a possible dependence on an increased activity of aspartate transcarbamylase for the subsequent rise in the level of nucleic acids in the mammary gland of the rat.