Development of Hypoxic Change of the Liver Cells as Revealed by the Isolated Perfused Rat Liver

In order to elucidate the development of hypoxic change of the liver cell, particularly vacuolar degeneration, perfusion experiments of the isolated rat liver, exposed to various degrees of hypoxia, were performed. Several parameters, such as hepatic blood flow, oxygen consumption and bile production of the liver, were examined with special reference to histological changes of the liver cell. At the initial stage of hypoxia, hepatic blood flow increased due to vasodilatative effect of hypoxia, and at the terminal stage of severe hypoxia for 50 minutes or longer, hydropic swelling of the liver cell and of the Kupffer's cell, being followed by rapid and marked decrease in hepatic blood flow, occurred. Although oxygen consumption and bile production of the liver perceptively decreased along with decrease in oxygen content of the portal vein blood, the liver cell unexpectedly maintained oxygen uptake and bile production. These data suggested that the liver cell was rather tolerant to hypoxic condition. Vacuolar degeneration of the liver cell developed by the combination of severe hypoxia and congestion, while each of them did not produce vacuolar degeneration. The factor, providing the preferential site of hypoxic change of the liver parenchyma, was discussed with particular reference to the hemodynamical characteristics of hepatic blood circulation.