To study the effects of glucagon-insulin (G-I) infusion on protein synthesis and DNA synthesis in a condition with partial hepatic ischemia, G-I or saline was infused via portal vein for 40 minutes before and after a period of partial hepatic ischemia or following a period of partial hepatic ischemia. Protein synthesis was measured by 14C-leucine incorporation into proteins in incubated liver slices and DNA synthesis by 3H-thymidine incorporation into DNA. Protein synthesis in the postischemic liver was significantly recovered faster and more completely in G-I treated rats. G-I infusion enhanced the DNA synthesis of postischemic liver significantly, peaking 48 hours after the period of partial hepatic ischemia. However, the dosage of G-I infused in this investigation couldn't increase the hepatic tissue blood flow measured by hydrogen gas clearance method. On the histological examination, mitotic index was significantly higher in G-I treated group than in control. These results suggest that G-I infusion could be beneficial effects on the liver in situation with partial ischemic injury and that G-I infusion could remarkably augment hepatic tissue repair following ischemic damage.