The Changes in Status of Antioxidant Defence System on Temporary Cerebral Ischemia and the Protective Effect of Vitamin E and C

Time-dependent changes in antioxidant defence system and the effect ofvitamin C and E supplementation on temporary cerebral ischemia wasinvestigated in this study. This study was performed in 140 male Wistaralbino rats weighting 300-400g. Before 30 minutes cerebral ischemiavitamin E (α-tocopherol) 10 mg/kg/day and vitamin C 30 mg/kg/day wereapplied intraperitoneally for a week period. Animals were sacrifiedfollowing 24 h and 72 h ischemia and the brain was removed as quick aspossible. Brain water content, süperoxide dismutase (SOD) ) and catalase(CAT) activities and the level of nonenzymatic antioxidant, reduced vitaminC and α-tocopherol levels were measured. Moreover the level ofmalondialdehyde (MDA) as an indicator of lipid peroxidation wasdetermined. At 24 h of reperfusion superoxide dismutase (SOD) andcatalase (CAT) activities, vitamin C and E level decreased significantly inischemic brain area (p<0.05, p<0.05, p<0.01 and p<0.01 respectively). After72 h of reperfusion SOD and CAT activities surpassed the pre-ischemiclevel (p<0.01 and p<0.05 respectively). The level of vitamin C and Eincreased significantly at 72 hours after ischemia but, did not reach preischemiclevels (p<0.01 and p<0.01 respectively). Administration of vitaminC and E a week before cerebral ischemia prevented the decrease in SODand CAT activities after 24 hours of reperfusion (p<0.01 and p<0.01respectively). Furthermore, the increase in ischemia induced lipidperoxidation and cerebral edema were decreased significantly byadministration of these vitamins (p<0.01 and p