Abstract
Our previous studies showed that exposure of rats to limited periods of cigarette smoke resulted in more severe myocardial damage when their hearts were subjected to myocardial ischaemia/reperfusion. The aim of this study was to determine whether supplementation of rats with antioxidant vitamins α-tocopherol and β-carotene was able to protect their hearts against the increase in ischaemia/reperfusion injury caused by smoke-exposure. The parameters measured were mitochondrial oxidative function, cellular levels of α-tocopherol and low molecular weight iron (LMWI). Supplementation with antioxidant vitamins resulted in significantly less mitochondrial functional oxidative damage compared to that observed in the controls. Supplementation did not affect the cellular LMWI content, suggesting that the generation rate of hydroxyl radicals was similar in both groups. The protective effect of α-tocopherol and β-carotene supplementation on the mitochondrial function against ischaemia/reperfusion could be due to their free radical scavenging action. Supplementation with antioxidant vitamins, therefore, had a beneficial effect on the excessive myocardial ischaemia/reperfusion injury of smoke exposed rats.