Studies in biochemical adaptation. The effect of variation in dietary protein upon the hepatic arginase of the rat

Abstract

The effects of variation in dietary protein upon hepatic arginase were studied in rats. The amt. of the enzyme, both absolute and in relation to unit weight of liver, hepatic N and body wt., increased with increase in dietary protein and reverted to normal with reversion to a normal diet. The adaptation to the increase or decrease in dietary protein was almost complete within 2 or 3 wks. of changing the diet. The rate and extent of increase of enzyme were greater in young animals than in older animals. There was a linear relationship between dietary protein and amt. of enzyme produced. This conformed with the mass action theory of enzyme adaptation (see preceding ).