The Acute Effects Of ATP-Sensitive Potassium Channel Opener (Pinacidil) And Blocker (Glimepride) On the Ischemia or Reperfusion-Induced Arrhythmias

Abstract

Introduction: Myocardial ischemia due to coronary obstruction and reperfusion due to the opening of the coronary vessel occurring in the acute stage of myocardial infarction leads to lethal arrhythmia and sudden death in humans. That is why pharmacological drug research to decrease these arrhythmias have been researched intensively. In this study, the effect of acute administration of pinacidil and glimepride, on ischemia or reperfusion-induced arrhythmia was aimed to be researched. Methods: Two groups were produced; In the first group, only ischemia was produced by the ligation of the left coronary artery in 20 minutes, and in the second group 6 minutes of ischemia by the ligation of the artery and the subsequent 15 minutes of reperfusion were produced by the opening of the occluded artery. Drugs were administered intravenously at 2 minutes of ischemia in the first group and just following the reperfusion in the second group. The ECG and blood pressure were recorded during ischemia and reperfusion. The type, duration, incidence of arrhythmia, heart rate, blood pressure, and the death rate from the recording were determined. All data were first compared by one-way ANOVA. Then, the drug groups with their control, and control and drug groups with each other were compared by a one-tailed student t-test. The incidence of arrhythmia and the death rate between groups was compared by the Ki square test. Results: Pinacidil significantly decreased the arrhythmia score both in the ischemia and reperfusion period but glimepiride was not effective when they were given intravenously in the acute stage of ischemia or reperfusion. Discussion and Conclusion: This study suggests that pinacidil might be a candidate for drugs that can be used to decrease arrhythmia in the acute stage of myocardial infarction but more study is needed to reveal the antiarrhythmic or proarrhythmic effect of glimepride in the acute stage of myocardial infarction.