INTRODUCTIONThe liver is one of the organs, which have potential regenerative capability in mammalian animal[1].The study of the canine model indicated that the liver could regenerate to original size after 70% hepatectomy in only two weeks[2]. So it is a hot research topic for the cellular and molecular mechanism of liver regeneration. Accumulated results demonstrated that the hepatocyte growth factor (HGF)[3], insulin-like growth factor Ⅰ and Ⅱ (IGF-Ⅰ, Ⅱ )[4], epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha)[5] and insulin[6] are among the most important growth factors for liver regenerative regulation. In recent years, a heat-stable protein in the serum of the patients with various liver diseases has been noted for its potential stimulation effects on the liver regeneration, and this growth factor is called hepatocyte-stimulatory substance (HSS).