Oxygen radicals and scavenger enzymes in ischaemia-reperfusion injury of skeletal muscle

Abstract

In this study the protective effects of removing oxygen free radicals during ischaemia and reperfusion of skeletal muscle were investigated. The bilateral gracilis muscle model was used in six dogs. Both muscles were made ischaemic for 4 h, followed by reperfusion for 60 min. To remove oxygen free radicals, superoxide dismutase and catalase were given 10 min before ischaemia and during the first 30 min of reperfusion in one muscle; the other muscle served as a control. Muscle blood flow was recorded during the first 35 min of reperfusion. At the end of reperfusion the contents of high-energy phosphates and glycogen were measured. Furthermore, the metabolic burst of leukocytes (chemiluminescence) was determined. Flow as well as creatine phosphate were always highest in the treated muscles as compared with the control muscles (p < 0.05). Adenosine triphosphate and glycogen were highest in all but one case. Spontaneous leukocyte chemiluminescence was significantly reduced in venous blood from the control muscle and insignificantly reduced in blood from the treated muscle as compared with blood from the aorta. The results are indirect evidence that reactive oxygen metabolites play a role in the genesis of ischaemia-reperfusion injury of skeletal muscle, and that treatment with scavenger enzymes may have protective effects.

Key Words:

• catalase
• injury
• ischaemia
• oxygen radicals
• reperfusion
• skeletal muscle
• superoxide dismutase