Inhibitory effect of melittin on Na^+ , K^+ -ATPase from guinea pig myocardial mitochondria  

蜂毒肽对豚鼠心肌线粒体Na^+、K^+-ATP酶的影响(英文)

作　　者：杨申[1] 张雪梅[1] 江明华[1] 

机构地区：[1]上海复旦大学药学院药理教研室,上海中国200032

出　　处：《Acta Pharmacologica Sinica》2001年第3期89-92,共4页中国药理学报（英文版）

基　　金：Project Supported by National Natural Science Foundation China, № 39770885.

摘　　要：AIM: To investigate the effect of melittin (Mel) of Na+ ,K+-ATPase activity and it's kinetic mode of action on guinea pig myocardial mitochondria. METHODS: Effect of Mel on heart mitochondria! Na+ , K+-ATPase activity was determined with colorimetry method. RESULTS; Mel inhibited Na+ ,K+ -ATPase in a concentration and time dependent manner, IC50, was 2.60 μmol/L. Kinetic studies of interaction between Mel and K+ , Na+ , ATP revealed that inhibitory effect of Mel was competitive with K+ , but not with Na+ and ATP. CONCLUSION: Mel polypeptide potently inhibits Na+ ,K+-ATPase, possibly by binding to the K+ site.目的:研究蜂毒肽对豚鼠心肌线粒体Na^+,K^+-ATP酶活性的影响。方法:应用光电比色法测定Na^+,K^+-ATP酶活性。以Line-weaver-burk双倒数作图法分析酶动力学参数。结果:蜂毒肽抑制心肌Na^+,K^+-ATP酶表现为浓度和时间依赖性,IC_(50)为2.60μmol/L。酶动力学研究表明,蜂毒肽对Na^+,K^+-ATP酶有抑制作用,对K^+表现为竞争性结合,对Na^+及ATP表现为非竞争性结合。结论:蜂毒肽对心肌Na^+,K^+-ATP酶有抑制作用,其抑制机制主要是与K^+竞争结合酶外侧的K^+结合位点。

关 键 词：MELITTIN bee venoms Na^+  K^+-exchanging ATPase myocardium mitochondna 

分 类 号：R285[医药卫生—中药学]