Oxygen-derived free radicals are important byproducts of abnormal oxidative metabolism during myocardial ischemic and reperfusion injuries.
The spin trapping ESR technique was applied to investigate oxygen-derived radicals in ischemic and post-ischemic rat hearts. Using 5,5'-dimethyl-l-pyrroline-N-oxide, carbon-centered radicals were identified during ischemia and oxy-radical adducts (superoxide anion radical, O.-2 and hydroxyl radicals, .OH) in post-ischemic rat heart. The formation of these spin adducts was inhibited by superoxide dismutase, suggesting that superoxide plays a role in the adducts' formation. The results demonstrate that oxygen derived free radicals are important byproducts of abnormal oxidative metabolism during myocardial ischemic and reperfusion injuries.
Arroyo et al. (Mon,) studied this question.