SUPEROXIDE-DISMUTASE AND ALLOPURINOL IMPROVE SURVIVAL IN AN ANIMAL-MODEL OF HEMORRHAGIC-SHOCK

We studied the efficacy of resuscitation with antioxidants in an anima l model of hemorrhagic shock. Male Sprague-Dawley rats were anesthetiz ed, and 27 mL/kg of blood was withdrawn from the carotid artery over 2 minutes. The animals remained in hemorrhagic shock for 45 minutes, fo llowed by 1 hour of resuscitation. Experimental groups were as follows : 1) 15,000 u/kg superoxide dismutase (SOD) in 54 mL/kg lactated Ringe r (LR); 2) 175,000 u/kg catalase (CAT) in LR; 3) 15,000 u/kg SOD + 175 ,000 u/kg CAT in LR; 4) allopurinol in LR; 5) deferoxamine bound to pe ntafraction (DFO), 27 mL/kg; 6) pentafraction alone; and 7) LR alone. Compared with resuscitation with LR alone, SOD and allopurinol improve d survival over 72 hours, P<0.05. Survival with SOD + CAT was not diff erent from LR alone. Deferoxamine bound to pentafraction did not incre ase survival over that with pentafraction alone. CAT had increased mor tality compared to LR, P<0.01. The efficacy of both SOD and allopurino l in decreasing mortality suggests the importance of superoxide radica ls after hemorrhagic shock and resuscitation. These and other antioxid ants are potential therapeutic agents in the clinical setting of traum a and hemorrhagic shock.