Analysis of the kinetics of the transition of cells to DNA synthesis in systems with stimulated proliferation. III. Regenerating liver

: The application of the previously reported methods of kinetic analysis to cell proliferation studies in the regenerating rat liver is under consideration. A fraction of hepatocytes (nearly 60% of the initial hepatocyte number) synchronously entering the mitotic cycle in response to partial hepatectomy has been discovered. The investigation of the temporal pattern of the kinetic criterium qS (t) allowed to make a detailed description of the main features of the transition of hepatocytes to DNA synthesis during the first 40 hours of liver regeneration. Using kinetic criteria of the initial and repeated entry of cells into S-period made it possible to reveal that the prereplicative period in the second mitotic cycle was shorter than that in the first one. Thus, the hypothesis about a special period which is necessary for the quiescent cell to acquire the competence to proliferation is additionally supported.