The acute combined effect of Pinacidil and Glimepiride on ischemia and reperfusion induced arrhythmia, “The Role of ATP- Dependent Potassium Channel”

Aim: In previous studies, it was shown that both Pinacidil and Glimepiride have antiarrhythmic action in their pretreatment before ischemia. But there was no study found about their combined effect on the arrhythmia in the acute stage of ischemia and reperfusion. That is why in this study the combined acute effect of these two drugs on these arrhythmias was aimed to be researched. Main Method: 26 Anesthetized male Sprague-Dawley rats aged 6-7 years have been used in this study. Ischemia was performed for 6 min. by the ligation of left main coronary artery reperfusion by releasing the silk thread on the artery. Results: Pinacidil alone was anti-arrhythmic in reperfusion period, while Glimepiride was pro-arrhythmic. The protective effect of Pinacidil was abolished by Glimepiride in combination group, and the expected protective results against I/R induced arrhythmia were not observed. Conclusion: The result of this study showed that combination of KATP channel opener and blocker given in different time during ischemia and reperfusion period do not have synergic effect to decrease the arrhythmia. This might be increasing heterogeneity in action potential duration in ischemic or normal myocardium.