RESUMO
<p><b>OBJECTIVE</b>To investigate the effect of S-allyl-L-cysteine (SAC) on isolated rat heart subject to ischemia/reperfusion(I/R) injury and the mechanisms.</p><p><b>METHODS</b>The isolated perfused rat hearts on a Langendorff apparatus were subjected to global ischemia for 30 min and followed by 120 min of reperfusion. Hemodynamic index, the production of formazan and the level of lactate dehydrogenase (LDH) in the coronary effluent were determined. Superoxide dismutase (SOD) and reactive oxygen species (ROS) in myocardial homogenates were measured.</p><p><b>RESULTS</b>Compared with I/R group, the hemodynamics were greatly improved, the production of formazan was increased, and LDH level in effluent was reduced in SAC group. SAC improved the SOD activity and significantly decreased the level of ROS. In addition, threonine (Thr) attenuated the protective effect of SAC significantly.</p><p><b>CONCLUSION</b>SAC has protective effect against myocardial ischemia/reperfusion injury on rats. The possible mechanism is that SAC be transported into the cell through alanine-serine-cysteine-transporter 1 (ASCT-1) improves SOD activity and reduces the level of ROS.</p>