钾通道激动剂对触发激动的实验研究  

The Experimental Study on the Effects of Potassium Channel Activators on Triggered Activity

作　　者：张宏艳[1] 范崇济[1] 李小梅[2] 张巧芳[1] 石军[1] 胡大一[3] 

机构地区：[1]天津市儿童医院内科,300074 [2]北京大学第一医院儿科 [3]北京大学人民医院心脏中心

出　　处：《天津医药》2004年第4期226-229,共4页Tianjin Medical Journal

基　　金：天津市科委自然科学基金 (项目编号 :993606811)

摘　　要：目的 :探讨ATP敏感性钾通道激动剂 (Cromakaliam,CRK)对豚鼠乳头肌动作电位及心室肌细胞ATP敏感性钾通道(KATP)的影响。方法:采用全细胞膜片钳技术及玻璃微电极方法,分别记录哇巴因(Ouabuain,OUB)、OUB加CRK对豚鼠乳头肌动作电位及心室肌细胞KATP 的影响。结果 :OUB诱发延迟后除极(DAD)及触发激动(TA),使静息膜电位增大自 ( -89±2)mV～( -76±9)mV ;CRK使静息膜电位减小自 ( -76±9)mV～( -90±3)mV,抑制DAD。CRK缩短动作电位时程(APD) ,使KATP 电流增大自 ( -120±17)pA～(342±89)pA。优降糖有拮抗CRK的作用。结论 :KATP 开放可以减弱哇巴因对心肌细胞的毒性作用 ,使APD缩短 ,中止DAD及触发激动 ,对心肌细胞具有保护作用。CRK的作用与增加KATPObjective:To investigate the effects of potassium channel activators (CRk) on action potential and ATP-sensitive potassium channel (KATP) in guinea pig papillary and ventricular myocytes.Methods: The effects of ouabuain and ouabuain plus CRK on action potential and KATP were recorded by whole cell patch clamp technique and standard glass microelectrode method.Results: OUB induced DAD, triggered the activity, and increased RP from (-89±2)mV to (-76±9)mV. CRK decreased RP from (-76±9)mV to (-90±3)mV,and inhibited DAD. CRK shortened APD, and increased KATP from(-120±17)pA to (342±89)pA. Glidiabet had resistant effect on CRK.Conclusion: Opening of KATP can decrease the poisonous effect of OUB on myocytes, shorten APD, end DAD, trigger activity, and also has the protective effect on myocytes. The effect of CRK is relative to increased KATP.

关 键 词：钾通道激动剂 触发激动 实验研究 电生理学 动作电位 心肌 

分 类 号：R329.2[医药卫生—人体解剖和组织胚胎学]