Effect of N-2-mercaptopropionylglycine in limiting myocardial reperfusion injury following 90 minutes of ischemia in dogs

Present study was designed to examine the effectiveness of N-2-mercaptopropionyl glycine (MPG) on oxygen free radical (OFR) mediated reperfusion injury. Twenty dogs underwent 90 min of left anterior descending (LAD) coronary artery occlusion followed by 4 h of reperfusion. In control animals (n = 12), 115 ml of saline was infused through left atrium at the onset of reperfusion whereas treated animals (n =8) received loading dose of MPG (40 mg/kg) infused through left atrium for 1 h followed by maintenance dose (25 mg/kg) for remaining 3 hours. Percentage area of necrosis vis-a-vis area at risk and percentage necrosis in left ventricular mass in MPG treated animals was significantly lower in comparison to control animals. Reperfusion in control group increased the lipid peroxidation and lowered glutathione (GSH) and superoxide dismutase (SOD) activity. MPG treatment significantly lowered the lipid peroxidation whereas GSH and SOD levels in necrotic zone were higher than in control. The above results suggest that MPG can offer a significant cardioprotection against oxidative stress in canine model.