[Myocardial tolerance to arrhythmogenic exposure and pharmacological activation of K(ATP)-channels in rats].

The cardioselective KATP channel activator BMS 180448 (3 mg/kg) administered intravenously 15 min before the coronary artery occlusion (10 min) decreased the incidence of ischemic and reperfusion arrhythmias in rats. A similar antiarrhythmic effect was observed when BMS 180448 was infused 2 min before reperfusion. Pretreatment with BMS 180448 also prevented the occurrence of CsCl induced arrhythmias, but but did not affect the incidence of epinephrine induced arrhythmias. On the contrary, BMS 180448 potentiated the arrhythmogenic action of CaCl2. The mechanism of the antiarrhythmic activity of BMS 180448 is discussed.