Free Oxygen Radicals at the Site of Ischecmia-Reperfusion Damage (Experimental study on rats)

Abstract

Purpose: The free oxygen radicals appearing after ischemia-reperfusion damage were researched in the blood, muscle and bone tissues of the rats. Material and
Method: The rats were divided into 3 groups as ischemia, ischemia-reperfusion and control groups. The ischemia group rats were clamped at the proximal of the femoral artery for about 2 hours; while the ischemia-reperfusion group rats were reperfused for about 45 minutes afler 2 hours ischemia. Result: ln the ischemia-reperfusion group, malonyldialdehyde level was found to be considerable elevated (p<0.05). Blood glutation peroxidase and catalase activities were considerable diminished in the ischemia group; while bone glutation peroxidase was diminished and catalase was significally incremented. When compared to the control group (p<0.05). Any kind of alteration was obtained in the muscle tissue.
Discussion: Free oxygen radicals react with proteins, nucleicacids, fipids and other molecular groups; and interfere with their metabolism and lead to cell membrane disruption and hence to cell death at this irreversible stage. There are a couple of sources to produce free oxygen radicals in the ischemic tissue. First one is the reaction chain between molecular oxygen and hypoxanthin facilitated by xanthin oxidase enzyme; second is the neutrophyl infiltration in to the ischemic tissue. At the ischemic stage, high energy phosphated-ATP converts into hypoxanthin. At the reperfusion stage; after abrupt and profuse oxygen influx, the protease activity increments and the reactions producing free radicals from hypoxanthin ensue. Progressive damage at reperfused tissues after ischemia was delineated in various viscera. Among these, skeletal muscle was found to be more resistant to ischemia than the other tissues.
Conclusion: The muscle tissue was found to be more resistant to ischemia-reperfusion damage in comparison to the other tissues.