SCAVENGING EFFECT OF CHINONIN ON NO AND OXYGEN-FREE RADICALS AND ITS PROTECTIVE EFFECT ON THE MYOCARDIUM FROM THE INJURY OF ISCHEMIA-REPERFUSION

The scavenging effect of Chinonin on NO and oxygen free radicals and i ts protective effect on myocardium from the ischemia-reperfusion injur y was studied with electron spin resonance (ESR) and chemiluminescence techniques. Chinonin can effectively inhibit the oxidative activity o f ONOO-, (the IC50 = 7 x 10(-5) mmol/L) and scavenge oxygen free radic als generated from the reaction of xanthine and xanthine oxidase (the IC50 = 2.5 x 10(-4) mmol/l). It is difficult to find another antioxida nt which can scavenge so effectively both ONOO- and oxygen free radica ls simultaneously. In the system of ischemia-reperfusion injury of myo cardium, Chinonin can, in parallel, scavenge the NO and oxygen free ra dicals generated from the ischemia-reperfused myocardium, and decrease the activities of lactate dehydrogenase (LDH) and creatine kinase (CK ) in the coronary artery effluent of ischemia-reperfused heart and the refore protect the heart from ischemia-reperfusion injury. The protect ive effect of 0.1 mmol/l Chinonin is similar to that of 1500 U/ml SOD and catalase.