Taurine at early reperfusion significantly reduces myocardial damage and preserves cardiac function in the isolated rat heart.

Objective: The Myocardial protective effects of taurine (TA) are well known. We investigated the optimal phase of giving taurine to reduce myocardial ischaemia-reperfusion injury in isolated rat hearts.

Methods: Isolated rat hearts were subjected to 20 min of global ischaemia followed by 60 min of reperfusion under three different conditions: global ischaemia alone (control group; n=8); pre-ischaemic administration of taurine (pre-TA group; n=8), perfusion with 10 mmol/L taurine for 10 min just before ischaemia; post-ischaemic administration of taurine (post-TA group; n=8), perfusion with 10 mmol/L taurine for the first 10 min of reperfusion. Ventricular functional and biochemical variables, the area at risk (AAR), and infarct size (IS) after reperfusion were compared between groups.

Results: Recovery of ventricular function in the post-TA group was significantly greater than that in the control and pre-TA groups in terms of left ventricular pressure and rate-pressure product. Lipid peroxide product as a marker of oxidant stress in the post-TA group was significantly less than that in the control and pre-TA groups. AAR relative to left ventricular area in the post-TA group was significantly less than that in the control and pre-TA groups. IS relative to AAR in the post-TA group was significantly less than that in the control group.

Conclusion: Taurine administered before or after ischaemia prevents infarction; being a potent free radical scavenging antioxidant, it reduced myocardial injury and provided significantly better functional recovery when given immediately after reperfusion.