[Pharmacologic control of reperfusion dysrhythmias]

The present study aims to investigate the effects of the lipophilic antioxidant Trolox C (a vitamin E analogue) and stobadine, a scavenger of free oxygen radicals, on reperfusion dysrhythmias. Experiments were performed on isolated perfused rat hearts subjected to global stop-flow ischaemia followed by reperfusion. Trolox C (10(-4 mol.l-1) and stobadine (10(-5) mol.l-1) were infused immediately prior to ischaemia. Trolox C (10(-4) mol.l-1) and stobadine (10(-5) mol.l-1) decreased the incidence and duration of reperfusion-induced dysrhythmias (quantified by the dysrhythmia score) in comparison to the ischaemic-reperfusion damaged hearts. There was an improvement in the recovery of contraction force and left ventricular diastolic pressure in Trolox or stobadine pretreated hearts. No significant changes in coronary flow resistance were observed. The results suggest that both substances protect the myocardium during ischaemic-reperfusion injury probably by affecting the generation and activity of reactive oxygen species.