Minimum sizes for remnant and transplanted livers in rats

Abstract

Our new technique of hepatectomy in rats, avoiding inferior vena cava constriction, revealed that 5%–10% of the total liver is the minimum required volume for remnant liver, a smaller amount than previously reported. The characteristic histological findings of remnant liver in perioperative death are marked hepatocytosis and hepatocyte apoptosis, and extensive hepatocyte necrosis with sinusoid congestion, all of which are thought to be caused by hyperendotoxemia and mitochondrial energy crisis. Partial liver transplantation in rats with our new technique of hepatectomy in the donor operation showed that a graft of 20% liver was the minimum required volume for successful transplantation, also a smaller amount than previously reported. There was no difference in the rate of increase in wet weight after surgery between 20% remnant liver and 20% transplanted liver. Differences between 10% minimum volume remnant liver and 20% minimum transplanted liver appeared to be caused by ischemia-reperfusion and cold preservation injury to the transplanted liver.