An Exerimental Study of the Liver Lysosomal Membrane Fragility During a Period of Partial Liver Ischemia and Following Blood Reperfusion

Ikuo Udagawa, Masaru Miyazaki, Hisao Koshikawa, Hiroshi Ito, Takashi Kaiho, Jun Matsumoto, Toshio Isono, Hiroyuki Suzuki, Takashi Koyama, Tsukasa Shimoda, Katsuji Okui

First Department of Surgery, School of Medicine, Chiba University

To examine the pathogenesis of liver ischemia more objectively, the change in liver lysosomal enzymes in a partial liver ischemic model in rats was studied. The free activity of the liver lysosomal enzyme and the lysosomal fragility index obtained from the ischemic lobe gradually increased after induction of ischemia and markedly increased after release of the clamp. There was a significant increase in free activity and fragility index of cathepsin D after two hours of reperfusion (0.52±0.05 units/mg protein and 41.2±3.7% respectively) compared to the preischemic values (0.27±0.4 units/mg protein and 28.5±2.5% respectively). In addition, serum lysosomal enzyme activity was markedly increased from 2.20±0.28 units/mg protein (preischemia) to 4.33±0.39 (after two hours of reperfusion). These results suggest that lysosomal labilization occurred in the ischemic lobe and that the lysosomal enzyme was released from the ischemic lobe into the serum. It is concluded that the lysosomal enzyme plays an important role in liver ischemic injury.

Key words
partial liver ischemia, lysosomal enzyme, lysosomal membrane, liver cell injury

Reprint requests
Ikuo Udagawa First Department of Surgery, School of Medicine Chiba University
1-8-1 Inohana, Chiba, 280 JAPAN

Accepted
June 13, 1990

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