Effect of desferrioxamine cardioplegia on ischemia-reperfusion injury in isolated rat heart.
Nicholson SC., Squier M., Ferguson DJ., Nagy Z., Westaby S., Evans RD.
BACKGROUND: The protective effect of desferrioxamine against myocardial ischemia-reperfusion injury remains uncertain. In this study we examined a broad range of ischemia-reperfusion indices to determine the effect of desferrioxamine cardioplegia in a model that reflects surgical practice. METHODS: Isolated rat hearts were subjected to 90 minutes of ischemia with cold cardioplegia, with or without 0.5-mmol/L desferrioxamine. Left ventricular mechanical function and the levels of thiobarbituric acid-reactive substances and nonprotein thiol compounds were measured after reperfusion. Electron microscopic analysis of mitochondria was performed using diaminobenzidine staining, together with histochemical staining for glycogen and marker enzymes in left ventricular muscle and the atrioventricular node. RESULTS: The desferrioxamine group showed better preservation of diastolic function (chamber stiffness coefficient at 15 minutes and maximum rate of decrease of left ventricular pressure at 45 minutes of reperfusion). Histochemical analysis showed that mitochondria-specific succinate dehydrogenase and the nonspecific esterase of the atrioventricular node were better preserved in the desferrioxamine group. CONCLUSIONS: The findings from this study indicate that there is added protection against ischemia-reperfusion injury when desferrioxamine is added to the cardioplegic solution; however, the study also highlighted that, in this clinically applicable model, desferrioxamine is not universally protective against all aspects of ischemia-reperfusion injury.