Effects of free radicals and oxidants on myocardial cellular injury.

Harmful effects of some biochemically generated free radicals and oxidants, including superoxide anions (O2-), hydroxyl radical (OH.), hydrogen peroxide, hypochlorous acid, and hypohalite radical, on isolated cardiac myocytes were compared in an attempt to identify the exact nature of the free radicals/oxidants responsible for myocardial ischemic-reperfusion injury. All of these free radicals/oxidants, with the exception of O2-, caused significant injury to the myocytes as evidenced by the enhanced lactate dehydrogenase and creatine kinase release as well as by morphologic examinations, simultaneously causing lipid peroxidation and oxidized glutathione release from the cells, OH. being the most detrimental of all.