Hepatorenal interaction in glutathione redox state during partial hepatic ischemia-reperfusion in rats

The hepatic glutathione metabolism during partial hepatic ischemia-reperfusion was studied in a rat model with special reference to the hepatorenal glutathione metabolism system. Bile samples, and in- and outflow blood and tissue samples of the rat liver, kidney and small intestine were collected during 60 min of 70% partial liver ischemia and reperfusion. Both reduced and oxidized glutathione levels were determined by HPLC. The tissue ratio of reduced to oxidized glutathione (GSH/GSSG ratio) decreased significantly in the ischemic hepatic lobe at 60 min after reperfusion. The GSH/GSSG ratio in bile from the ischemic hepatic lobes decreased significantly after 60 min of ischemia and gradually recovered after reperfusion. The net release of GSH from the nonischemic hepatic lobe increased at 60 min after reperfusion, since the calculated net release of GSH from the whole liver increased significantly whereas there was no change in the net release from the ischemic hepatic lobe. The tissue GSH level in the kidney increased significantly at 180 min after reperfusion. The calculated net uptake of GSH into the kidney, and the net release of total cysteine from the kidney, tended to decrease at the end of 60 min of ischemia, to increase at 60 min after reperfusion and then decrease at 180 min after reperfusion. We found that the hepatorenal glutathione metabolism was changed by partial hepatic ischemia-reperfusion. These changes might reflect a hepatorenal interaction to maintain the glutathione redox state of the vital organs.