There is a growing body of evidence for the role of free radicals in mediating myocardial
tissue injury during myocardial ischemia and in particular during the phase of myocardial
reoxygenation. Associated with myocardial ischemia and reperfusion is the generation of
oxygen-derived free radicals from a variety of sources that include the mitochondrial electron
transport chain; the biosynthesis of prostaglandins; the enzyme xanthine oxidase; and
circulating elements in the blood, with the polymorphonuclear neutrophil assuming a …