[Metabolism and modification of high mobility proteins (HMG) in the liver of rats of various age].

It is shown that heterogeneity of the high-mobility -group proteins (HMG-proteins) in the rat liver does not depend on the animal age, while relative content of certain classes of these proteins and the HMG-proteins H1 histones ratio obeys age specificity. Metabolism of HMG 1 and 2 proteins in animals who have not achieved sexual maturity is low; the intensity of inclusion of labelled predecessors to proteins HMG 14', 17 and 17' decreases in the postnatal ontogenesis. The highest of HMG-proteins is observed in the liver of young (3 months) animals. In old (24 months) rats this process is inhibited. At all the stages of postnatal ontogenesis in the ribosylation intensity of HMG-proteins 14', is higher than that of the other classes of these proteins. The intensity of ribosylation of most fractions of HMG-proteins increases after 12 months.