Some aspects of the regulation of hepatocyte proliferation.

Studies of hepatocyte proliferation during physiologic growth of the rat and after experimental stimulations such as partial hepatectomy and injection of irritants show that an inhibitory mechanism is associated with decreasing proliferation and causes hepatocytes to be less sensitive to mitotic stimuli. An inhibitory glycopeptide linked to a high molecular weight protein, alpha 2-macroglobulin in man, has been characterized. This glycopeptide blocks the cell cycle of hepatocytes at the G1-S transition in vivo.