years ago, Noma first applicated the patch\|clamp technique to CN\|treated mamammalian heart cells,evealed specific K + channels which were depressed by intracellular ATP at level greater than 1 mM.He suggested the ATP-sensitive channels are important for regulating cellular energy metabolism in the control of membrane exitability.Recent studies supported the hypothesis and suggested that ATP-sensitive channels play an important role in hypoxia,myocardial ischemia/reperfusion and is chemic preconditioning.

AIM: To determine the effects of phospholipase A 2 (PLA 2) and K ATP on rat ischemia/reperfusion(I/R)-induced arrhythmia. METHODS: Myocardial ischemia and reperfusion were produced by occlusion and reirregation of the left anterior descending artery(LAD). An inhibitor of PLA 2, 5,5-dithio-bis(2-nitrobenzoic acid) (DTNB) (16 mg /kg), a K ATP opener pinacidil (0.2 mg/kg), a K ATP blocker glibenclamide (0.3 mg/kg) was used 5 min prior to 10 min regional ischemia and 10 min reperfusion. RESULTS: DTNB (16 mg/kg) reduced the scores of arrhythmia, creatine kinase (CPK) and lactate dehydrogenase(LDH) (P