INTERMITTENT ANOXIA REDUCES OXYGEN-FREE RADICALS FORMATION DURING REOXYGENATION IN RAT HEPATOCYTES

The sensitivity of liver sells to anoxia is a major problem afflicting liver preservation and transplantation. Intermittent ischemia has bee n proposed to reduce reperfusion injury. The aim of the study was to a ssess oxygen free radical formation and cell injury during continuous or intermittent anoxia/reoxygenation in rat hepatocytes. Anion superox ide was measured by lucigenin-enhanced chemiluminescence and cell dama ge by LDH release and trypan blue uptake. During anoxia, superoxide ge neration dropped to background level in both groups; trypan blue uptak e and LDH release, which increased progressively, were significantly g reater in hepatocytes exposed to continuous compared to intermittent a noxia. During reoxygenation, a massive generation of superoxide anion formation, followed by a sharp increase in LDH release, was observed i n both groups. However, both oxyradical generation and cell injury wer e significantly greater in cells exposed to continuous compared to int ermittent anoxia. The data, showing that intermittent oxygen deprivati on reduce liver cell injury and oxygen free radical formation determin ed by anoxia/reoxygenation, suggest a novel possible approach to the r eduction of reperfusion injury. (C) 1997 Elsevier Science Inc.