磷酯酶A_2抑制剂DTNB对大鼠心肌缺血再灌注心律失常的影响  

The effect of phospholipase A_2 inhibitor DTNB on the rat ischemia reperfusion arrhythmia

作　　者：孟繁学[1] 焦晓慧[1] 韩大英[1] 

机构地区：[1]首都医科大学心血管生理研究室,北京100054

出　　处：《中国病理生理杂志》2000年第3期222-225,共4页Chinese Journal of Pathophysiology

摘　　要：目的 :研究非钙依赖性的磷脂酶A2 (PLA2 )和ATP敏感性钾通道 (KATP)在大鼠心肌缺血再灌注(I/R)心律失常中的作用。方法 :结扎大鼠左冠状动脉前降支造成缺血 10min ,然后放开再灌注 10min。在心肌缺血前 5min分别给予PLA2 抑制剂 5 ,5 -dithio -bis(2 -nitrobenzoicacid) (DTNB) (16mg/kg) ,KATP开放剂pinacidil(0 2mg/kg) ,KATP阻断剂glibenclamide(0 3mg/kg)。结果 :与对照组相比 ,DTNB可降低心律失常评分、磷酸肌酸激酶 (CPK)和乳酸脱氢酶 (LDH)值 (P <0 0 5 ) ;而glibenclamide对I/R心律失常无影响 ,但升高CPK ,LDH值 (P<0 0 5 ) ;与glibenclamide组比 ,在glibenclamide阻断KATP后 ,DTNB可引起致死性心律失常 ,并可升高LDH值 (P<0 0 5 ) ;pinacidil可完全抑制I/R引起的室颤和室速。结论 :PLA2 抑制剂DTNB可减轻I/R损伤 ,表明PLA2 在I/R心律失常中起着重要作用 ,同时也表明激活的KATP具有抗I/R心律失常的作用。但DTNB对抗I/R心律失常的作用与KATP的关系仍有待进一步研究。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<0.05). Glibenclamide had no effect on I/R arrhythmia, but increased CPK and LDH (P<0.05). After K ATP was blocked by glibenclamide, DTNB led to lethal ventricular fibrillation and increase LDH, higher than without DTNB (P<0.05). Pinacidil depleted ventricular fibrillation and ventricular tachycardia. CONCLUSIONS: PLA 2 inhibitor DTNB enhances membrane stability both in structure and function, so that reduces myocardial damage caused by I/R, and suggests that PLA 2 plays an important role on myocardial I/R arrhythmia, and also implies that activated K ATP prevents rats from I/R arrhythmia under condition of our experiments, but the relationship between DTNB protective effect and K ATP activity remains indefinite.

关 键 词：心律失常 磷脂酶A类 心肌缺血 DTNB 

分 类 号：R542.206[医药卫生—心血管疾病] R541.705[医药卫生—内科学]