[Glycogen concentration in DNA-synthesizing and non-DNA-synthesizing hepatocytes of week-old rats].

Using the combined cytochemistry, that allows to determine glycogen and DNA contents, and to localize 3H-thymidine label in one and the same cell, glycogen content was measured in both 3H-TdR-marked and 3H-TdR-non-marked hepatocytes of week-old rats. The vast majority of hepatocytes in a liver population of such rats are mononuclear 3H-TdR-non-marked cells with a 2C DNA content, which corresponds to the diploid chromosome set. The ratio of binuclear hepatocytes with diploid nuclei is in average 0.6%. At one injection of 3H-TdR, 6.6% of hepatocytes are marked in average which are almost exclusively mononuclear cells with 2c to 4c DNA content. In binuclear hepatocytes with two diploid nuclei (2c X 2), the label was seen only in single instances. The average glycogen content in S-phase hepatocytes is aproximately one third of that in hepatocytes that did not start DNA synthesis (G1 and G2 phases). The glycogen content in hepatocytes is seen reducing during S-phase. The glycogen content in G2-phase hepatocytes does not differ from that of hepatocytes before they start DNA synthesis. The availability of glycogen is not necessary for the beginning of S-phase: DNA synthesis in hepatocytes of week-old rats can start and proceed irrespective of the presence of glycogen in these. The glycogen content in binuclear hepatocytes with diploid nuclei that did not start DNA-synthesis is twice as much as in mononuclear hepatocytes before they started DNA synthesis.