E-4031 enhanced Ca^(2+) transient and ventricular myocytes contraction via reverse mode Na^+/Ca^(2+) exchange in normal and hypertrophic rats  

E-4031通过反向钠钙交换增加正常和心肌肥厚大鼠心肌细胞钙瞬变和收缩(英文)

作　　者：崔香丽[1] 赵录英[1] 吴博威 

机构地区：[1]山西医科大学生理教研室,太原中国030001

出　　处：《Acta Pharmacologica Sinica》2002年第9期31-36,共6页中国药理学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China,№ 30170346.

摘　　要：AIM: To study the effects of N-[4-[1-[2-(6-methyl-2-pyridinyl)ethyl]-4-piperidinyl]carbonyl]phenyl] methanesulfonamide dihydrochloride dihydrate (E-4031), a specific Ikblocker, on Ca2= transient and cell contraction of normal and hypertrophied rat ventricular myocytes. METHODS: Electrically triggered Ca2= transient and cell shortening were measured simultaneously using the Ion Imaging System with charge coupled digital (CCD) camera. RESULTS: E-4031 (10 μmol/L) increased Ca2= transient and cell shortening from (210?9) and (3.0?.8) urn to (245?7) and (3.6?.0) μm, respectively (P【0.05) in normal cardiomyocytes and from (196?4) and (3.0?.3) μm to (240?9) and (3.6+1.3) μm respectively (P【0.05) in hypertrophied cardiomyocytes, while did not change calcium sensitivity in both groups. KB-R7943 completely blocked the activating effects induced by E-4031 in both of normal and hypertrophied cardiomyocytes. Nicardipine did not block the increasing effects of E-4031. CONCLUSION: E-4031 increased Ca2+ transient and cell contraction via stimulating reverse mode of Na+/Ca2= exchange while without influencing calcium sensitivity. These effects were more notable in hypertrophied cardiomyocytes than in normal myocytes.目的:观察I_K阻断剂E-4031对正常和心肌肥厚大鼠钙瞬变和细胞收缩的影响.方法:应用带CCD Cam-era的离子影象分析系统(Ion Imaging System)测定离体大鼠心肌细胞钙瞬变和细胞长度.结果:E-4031(10 μmol/L)分别使正常组钙瞬变和细胞缩短从对照组的(210±49)和(3.0±0.8)μm增加到(245±47)和(3.6±1.0)μm(P<0.05),使心肌肥厚组钙瞬变和细胞缩短分别从对照组的(196±54)和(3.0±1.3)μm增加到(240±49)和(3.6±1.3)μm(P<0.05),而对钙敏感性无显著影响.KB-R7943可完全阻断正常组和肥厚组心肌细胞由E-4031诱导的激动作用.尼卡地平不能阻断E-4031的增加作用.结论:E-4031可通过刺激反向钠钙交换增加正常和心肌肥厚大鼠心肌细胞钙瞬变和细胞收缩,同时并不影响钙敏感性.且对肥厚心肌细胞的影响大于正常心肌细胞.

关 键 词：E-4031 FURA-2 calcium CONTRACTION electric stimulation Na⁺/Ca²⁺ exchange CARDIOMEGALY 

分 类 号：R96[医药卫生—药理学]