Spin trapping of oxygen and carbon-centered free radicals in ischemic canine myocardium

Oxygen free radical injury has been postulated to occur during myocardial ischemia. We have used Electron Spin Resonance and Spin Trapping techniques to directly demonstrate the production of carbon-centered (R.) and oxygen-centered lipid radical (RO.) in ischemic canine heart. In addition, venous effluent from the ischemic region showed that conjugated dienes (lipid peroxidation products) increased with ischemic duration. Our results suggest that the formation of the oxygen-centered and carbon-centered lipid radical species during ischemia are a consequence of oxy-radical peroxidation of myocardial membrane lipids.