Oxygen-derived free radical scavengers and skeletal muscle ischemic/reperfusion injury.

Total injury in ischemic skeletal muscle is a function of ischemic damage and reperfusion injury. In an attempt to decrease reperfusion injury, we gave the oxygen-derived free radical scavengers allopurinol, superoxide dismutase, or mannitol during reperfusion of canine gracilis muscle made ischemic for 4 hours. We measured muscle O2 consumption (MVO2), and tissue calcium, water, and adenosine triphosphatase (ATP) before ischemia, after ischemia, and at 5 minutes and 60 minutes of reperfusion. The results at 60 minutes showed no improvement in MVO2 or ATP. In fact, ATP was significantly depressed with allopurinol and superoxide dismutase treatment, and tissue edema did not decrease in any of the groups. We conclude that the simple addition of oxygen-derived free radical scavengers during the initial reperfusion of totally ischemic skeletal muscle does not attenuate reperfusion injury.