人心肌细胞缓慢激活延迟整流钾电流细胞模型的建立  

Establishment of cell model of human cardiomyocyte slowly activating delayed rectifier potassium current

作　　者：孙冬冬[1] 王晓斌[2] 赵志敬[1] 李志超[2] 朱妙章[3] 贾国良[1] 王海昌[1] 董明清[2] 

机构地区：[1]第四军医大学西京医院心血管内科,陕西西安710032 [2]第四军医大学基础部病理生理学教研室,陕西西安710032 [3]第四军医大学基础部生理学教研室,陕西西安710032

出　　处：《心脏杂志》2007年第1期28-31,35,共5页Chinese Heart Journal

基　　金：国家自然科学基金项目资助(No.30400155)

摘　　要：目的建立稳定表达人心肌细胞缓慢激活延迟整流钾电流(IKs)的细胞模型。方法编码IKs通道α亚单位的KCNQ1基因及β亚单位的KCNE1基因共转染HEK 293细胞,潮霉素B筛选,电生理学及药理学方法鉴定。结果KCNQ1/KCNE1基因被成功转入HEK 293细胞,KCNQ1/KCNE1电流与人心肌IKs电流具有相似的电流特性;hKCNQ1/hKCNE1通道反转电位与细胞外钾离子浓度呈线性关系;选择性IKs通道阻断剂Chromanol 293B对KCNQ1/KCNE1电流具有明显而可逆的抑制作用,其IC50(+40 mV)为9.1μmol/L;无钾细胞外液可以增加KCNQ1/KCNE1电流幅度,+40 mV时电流幅度增加(28.6±2.0)%(P<0.01,n=8),但对其动力学特性无明显影响。结论已经成功构建稳定表达人心肌KCNQ1/KCNE1通道蛋白的HEK 293细胞系,其电生理学特性和药理学特性与人心肌IKs相似,可以作为研究人心肌IKs的细胞模型。AIM To establish a cell model of human cardiomyocyte delayed rectifier potassium current （IKs）. METHODS Human cardiac KCNQ1 and KCNE1 genes, which encode α and β subunit of IKs respectively, were cotransfected into HEK 293 cells. Hygromycin B was used to screen the transfected cells. Electrophysiological method was used to identify stably expressing KCNQ1/KCNE1 HEK 293 cell clones. RESULTS KCNQ1/KCNE1 genes were successfully transfected into HEK 293 cells. The KCNQ1/KCNE1 currents had similar characteristics of native human IKs. Its reverse potential was linearly correlated with the extracellular potassium ions. The currents were significantly and reversibly inhibited by Chromanol 293B, a specific IKs blocker, with an IC50 of 9.1 μmol/L. Extracellular fluid without potassium ions significantly increased the magnitude of IKs but had no effects on its kinetics. At ＋ 40 mV, the increased level was （28.6 ±2.0） % （ P 〈 0.01, n = 8 ）. CONCLUSION HEK 293 cell model stably expressing human cardiac KCNQ1/KCNE1 channels has been successfully established, which has similar characteristics of native human cardiac IKs. The established cell model is an ideal cell model of human cardiac IKs.

关 键 词：缓慢激活延迟整流钾电流 KCNQ1/KCNE1 HEK 293细胞系 

分 类 号：R331.38[医药卫生—人体生理学]