Reactive Oxygen Species Production in the Isolated Perfused Rat Liver: Effect of Respiratory Inhibitors.

Abstract

Mitochondria are one of the possible sources of potentially harmful reactive oxygen species in tissue during ischemia-reperfusion. In order to delineate the capacity of the respiratory chain to produce reactive oxygen species, the effect of respiratory inhibitors on the oxygen uptake and luminol and lucigenin enhanced chemiluminescence was measured in isolated blood-free perfused rat livers. Concomitant tissue damage was monitored by measuring the release of lactate dehydrogenase and thiobarbituric acid reactive substances by the livers. Cyanide inhibited oxygen uptake reversibly while rotenone and Antimycin A effects were not reversible. Enhanced chemiluminescence was increased immediately by cyanide, suggesting increased formation of reactive oxygen species. Antimycin A produced a delayed, large increase in chemiluminescence concurrent with severe cell damage and increased lipid peroxidation; Cyanide and rotenone induced only limited cell damage. The cell damaging effect of Antimycin A was delayed by the simultaneous administration of cyanide. These results are discussed in terms of the possible role of reactive oxygen species produced during Antimycin A inhibition of the respiratory chain in cell damage.