RAT HEPATOCYTES ISOLATED FROM ALCOHOL-INDUCED FATTY LIVER HAVE AN INCREASED SENSITIVITY TO ANOXIC INJURY

The aim of this study was to determine whether rat hepatocytes isolate d from steatotic or nonsteatotic Livers have different thresholds for injury due to anoxia-reoxygenation. Rats were fed ethanol or control d iets for 8 weeks. Histology showed that more than 75% of the hepatocyt es in alcohol-fed and less than 3% in control animals contained fatty vacuoles. The glycogen content was significantly reduced in steatotic livers. Isolated hepatocytes were cast in agarose gel threads and perf used with Krebs-Henseleit bicarbonate buffer. Cell viability was deter mined by Trypan Blue (TB) exclusion; cell injury was determined by lac tate dehydrogenase (LDH) release; and superoxide anion (O-2(.-)) was d etermined by lucigenin enhanced chemiluminescence (LCL). During the pr e-anoxic basal perfusion the following occurred: viability was 86% +/- 1% and 85% +/- 1%; LDH release was 16 +/- 3 and 15 +/- 3 mU/min; and LCL was 4 +/- 1 and 5 +/- 1 nA in steatotic and nonsteatotic hepatocyt es, respectively. Cell viability decreased slightly under 4 hours of a erobic perfusion without differences between the two groups. In contra st, fatty hepatocytes died much faster than did control hepatocytes du ring anoxia; after 3 hours viability was 17% +/- 8% vs. 60% +/- 2% (P < .001), respectively. With reoxygenation following 2 hours of anoxia, the changes in viability, in LDH release, and in LCL were similar in both groups. These results indicate that in hepatocytes isolated from alcohol-fed rats when compared with control hepatocytes: 1) cell viabi lity under aerobic conditions is not influenced; 2) anoxic injury is s ignificantly increased; 3) a reduction in the hepatic glycogen stores, which may contribute to the enhanced sensitivity to anoxia, can be de monstrated; and 4) O-2(.-) generation and cell injury occurring immedi ately after reoxygenation do not appear to be affected.