[Distribution of H3-hydrocortisone in subcellular fractions of the liver of rats of different ages].

The paper is concerned with the results of a study of the distribution of /3H/-hydrocortisone in hepatocytic organellae of adult and old rats. In subcellular fractions /3H/-hydrocortisone was distributed inhomogeneously: the greatest number of tracers was detected in the cytosol, less in microsomes, mitochondria, nuclei. Age differences are absent. Intranuclear distribution of the hormone is the following: low activity chromatin greater than active chromatin greater than heterogeneous sediment (including the matrix and nuclear membrane). In mitochondria the least number of tracers was detected in inner membrane, and in outer membrane and matrix the distribution was almost the same. The determination of specific radioactivity of /3H/-hydrocortisone permitted the detection of an increase in this index in low activity chromatin and a decrease in mitochondrial inner membranes and matrix.