SERUM HEPATOCYTE GROWTH-FACTOR ACTIVITY AND HEPATOCYTE PROLIFERATION IN LONG-EVANS WITH A CINNAMON-LIKE COAT COLOR RATS WITH HEPATIC-LESIONS

We classified hepatic lesions spontaneously developed by Long-Evans wi th a cinnamon-like coat color (LEC) rats into the following four stage s: Normal liver, acute hepatitis, chronic hepatitis, and hepatoma, by biochemical tests of the sera, and anatomical and histopathological ex amination of the livers. Hepatocyte growth factor (HGF) activity in th e sera of LEC rats which developed acute hepatitis, chronic hepatitis, and hepatoma was higher than that of normal LEC rats. In paticular, H GF activity in the sera of the LEC rats,vith acute hepatitis was about 70-fold that of normal LEC rats. However, primary cultured hepatocyte s of LEC rats with hepatic lesions were hardly proliferated by stimula tion with EGF and insulin in vitro or with increased HGF in vivo. Thes e results suggest that the hepatocytes of LEC rats with hepatic lesion s disorder the signal transduction of growth factors.