Effect of vitamins A and E on ischemia-reperfusion damage in rabbit heart

The aim of this study was to test the effect of vitamins A and E in reducing oxyradical effects and myocardial damage after ischemia-reperfusion in the rabbit heart. Oxyradical effects were indirectly assessed by hydroperoxide initiated chemiluminescence and myocardial damage was evaluated by qualitative and quantitative electron microscopy. Left anterior coronary artery was ligated in control and vitamin-treated rabbits for 30 min and then reperfused for 10 min. Rabbits were pretreated with 150 mg vitamin E and 60,000 IU vitamin A 24 h before surgery. After 10 min of reperfusion full-thickness needle samples were obtained from five different myocardial areas (three ventricular and two septal areas) and used for the determination of hydroperoxide-initiated chemiluminescence and ultrastructural damage. In the control group, hydroperoxide-initiated chemiluminescence was 18,400 +/- 500 cpm/mg protein for the non-ischemic and non-reperfused ventricular areas, and 40,500 +/- 1,800 cpm/mg protein for ischemic-reperfused ventricular areas. In the vitamin-treated group, hydroperoxide-initiated chemiluminescence was decreased by 8% in the non ischemic and non reperfused ventricular areas and by 51-75% in the ventricular ischemic and reperfused areas. The two septal areas in the control group gave chemiluminescences of 6,800 +/- 1,200 cpm/mg protein (non ischemic-non reperfused) and 17,000 +/- 2,000 cpm/mg protein (ischemia-reperfusion). In the vitamin-treated group, chemiluminescence decreased by 4 and 58%, respectively. The ischemia-reperfused areas showed extensive edema, margination of nuclear chromatin and swollen mitochondria with disrupted cristae including rupture of the inner and outer mitochondrial membranes.(ABSTRACT TRUNCATED AT 250 WORDS)