Peculiarities of liver regeneration in Chinese hamster Cricetulus griseus

Abstract

With the aid of cytofluorimetry and interference microscopy, the ploidy level and the hepatocyte ploidy class distribution were studied and the dry mass of hepatocytes was measured in hepatocytes in liver of Chinese hamsters Cricetulus griseus and of Balb/c mice before and one month after partial hepatectomy. The mean ploidy level in hepatocytes of the Chinese hamster normal liver amounted to 2.35 ± 0.03 c. The modal class was mononuclear hepatocytes with diploid nuclei (82.4 ± 1.3%). The mean dry mass of hepatocytes amounted to 605.2 ± 4.8 pg. In the process of liver regeneration in the Chinese hamsters, the ratio of ploidy classes and the hepatocyte dry mass did not change. After a similar liver resection in the mice, a significant polyploidization of liver parenchyma occurred. The mean ploidy level in hepatocytes rose by 32%. Instead of 4cx2-hepatocytes, the modal class became mononuclear octaploid cells the relative portion of which increased, on average, by five times. The portion of binuclear hepatocytes with octaploid nuclei in mouse liver rose by more than five times. Thus, in the Chinese hamsters Cricetulus griseus, unlike mice, regeneration of liver occurred exclusively at the expense of proliferation of hepatocytes.