dc.description.abstract | Objectives: In the present study, effects of hydroalcoholic extract of grape seed (GSE) on ischemia-reperfusion (I/R)- induced infarct size and cardiac arrhythmias were investigated in isolated rat heart. Methods: Isolated rat hearts were divided into four groups and mounted on a Langendorff apparatus at constant pressure, then subjected to 30 min regional ischemia followed by 120 min reperfusion. In control group, the hearts were perfused by a modified Krebs-Henseleit solution throughout the experiment, however, in the test groups they were perfused by enriched Krebs solution with GSE (1, 10 and 100 ?g/ml) during I/R. The ECGs were recorded and analyzed to determine cardiac arrhythmias. Infarct size was determined by computerized planimetry method. Results: The results demonstrated that perfusion of GSE produces significant reduction in infarct size in isolated rat heart. In the control group, infarct size was 31±5 %, while perfusion of GSE (1, 10, and 100 ?g/ml) reduced it to 12±3 (P<0.05), 16±6 (P<0.05) and 2±1 % (P<0.01), respectively. The extract (1 ?g/ml) caused significant reduction (P<0.05) in the number, duration and incidence of ischemic ventricular tachycardia (VT). At the reperfusion phase, low concentrations of GSE (especially 1 ?g/ml) showed the same effects as well as significant reduction (P<0.05) in the number of ventricular ectopic beats (VEBs). Conclusion: Results of this study showed cardioprotective effects of GSE against I/R injuries by reduction of infarct size and arrhythmias. Maybe, the presence of proanthocyanidin (as free radical scavenging agent) and reduction of intracellular calcium ions may involve in these protective effects. | |