Studies of liver phosphorylase in hepatic injuries II. Alteration in isozyme pattern

Enzyme deviations in injured livers were studied by analyzing isozyme patterns of phosphorylase using a newly developed electrophoretic method, which separates six molecular species of this enzyme, i.e. M,FM,F,L,L', and FL'. In hepatic injuries caused by CCl4 and galactosamine intoxications of rats, F appeared in early stages and L' (and FL') in later stages of the injuries with a concurrent decrease or loss of L, which is a sole isozyme component of adult liver. In injured livers of patients with hepatitis and cirrhosis of the liver, increases in FL' activity were also found. Appearance of F was found only in hepatocellular carcinoma. The results obtained with phosphorylase isozyme analysis support the idea that an undifferentiated gene expression takes place in the injured livers of non-malignant hepatic disorders.