不同浓度氯普鲁卡因对HEK2936细胞KCNQ2/Q3通道电流的影响  

Effects of different concentrations of chloroprocaine on KCNQ2/Q3 channel currents in HEK2936 cells

作　　者：秦士吉[1] 李军[2] 李红[2] 李明[1] 张凡[3] 赵森明[2] 程艳欣[2] 

机构地区：[1]河北医科大学第三医院骨科,石家庄市050051 [2]河北医科大学第三医院骨科疼痛科,石家庄市050051 [3]河北医科大学药理学教研室

出　　处：《中华麻醉学杂志》2013年第8期944-947,共4页Chinese Journal of Anesthesiology

基　　金：河北省科技支撑项目（092061112D）

摘　　要：目的 评价不同浓度氯普鲁卡因对人胚胎肾细胞（HEK2936细胞）KCNQ2/Q3通道电流的影响.方法 以HEK293细胞作为表达体系,用脂质体交KCNQ2/3钾离子通道基因和绿色荧光蛋白转染至HEK293细胞,使细胞表达KCNQ2/Q3通道.第一部分：采用随机数字表法,将转染后的HEK293细胞分为4组（n=11）：对照组、1、10和100 mmol/L氯普鲁卡因组,记录不同钳制电压（-40、0、40 mV）下HEK293细胞KCNQ2/Q3通道电流,作用时间为1 min.第二部分：采用随机数字表法,将转染后的HEK293细胞分为2组（n=5）：对照组（C组）和10 mmol/L氯普鲁卡因组（L组）,记录不同钳制电压（-80 ～ 30 mV）下HEK293细胞KCNQ2/Q3通道电流,作用时间为1 min.采用单指数方程对通道激活段和去活段进行拟合,计算KCNQ2/Q3通道激活时间常数和去活时间常数.不同激活电压下所获去活尾电流统一标准化后经Boltzmann方程拟合,得到KCNQ2/Q3通道电流-激活电压关系曲线（即通道Ⅰ-Ⅴ曲线）.结果 第一部分：钳制电压-40、0和40 mV时,1、10和100 mmol/L氯普鲁卡因组HEK293细胞KCNQ2/Q3通道电流抑制率高于对照组（P＜0.05或0.01）.第二部分：与对照组比较,钳制电压0 mV时10 mmol/L氯普鲁卡因组KCNQ2/Q3通道激活时间常数延长,钳制电压-80 mV时KC-NQ2/Q3通道去活时间常数缩短,KCNQ2/Q3通道半数激活电压升高,向去极化移动,Ⅰ-Ⅴ曲线斜率减小（P＜0.05）.结论 氯普鲁卡因呈浓度依赖性抑制HEK2936细胞KCNQ2/Q3通道电流；氯普鲁卡因可延迟KCNQ2/Q3通道开放,提前关闭,使KCNQ2/Q3通道活性降低.Objective To evaluate the effects of different concentrations of chloroprocaine on KCNQ2/Q3 channel currents in HEK2936 cells.Methods Human embryonic kidney （HEK293） cells served as an expression system.KCNQ2 and KCNQ3 cDNAs and green fluorescent protein were transfected into HEK293 cells by using lipofectamine.The KCNQ2/Q3 currents were recorded by using the whole-cell patch-clamp technique.Part Ⅰ The transfected HEK293 cells were randomly divided into 4 groups （n =11 each）：control group,and 1,10 and 100 mmol/L chloroprocaine groups.The KCNQ2/Q3 channel currents produced by different concentrations of chloroprocaine were recorded under different holding potentials （-40,0 and 40 mV） and the action time was 1 min.Part Ⅱ The transfected HEK293 cells were randomly divided into 2 groups （n =5 each）：control group and 10 mmol/L chloroprocaine.The KCNQ2/Q3 channel currents were recorded under different holding potentials （-80-30 mV）and the action time was 1 min.Different test potentials were normalized and fitted to Boltzmann function,and KCNQ2/Q3 channel Ⅰ-Ⅴ curve was then obtained.The activation and deactivation currents were both fitted to a single exponential function and the time constants for current activation and for current deactivation were calculated.Results Part Ⅰ When the holding potential was 40,0 and-40 mV,the suppression rate of KCNQ2/Q3 channel currents in HEK293 cells was higher in 1,10 and 100 mmol/L chloroprocaine groups than in control group （P ＜0.05 or 0.01）.Part Ⅱ Compared with control group,the time constant for the current activation at 0 mV of holding potential was prolonged,the time constant for the current deactivation was shortened when the holding potential was-80 mV,and the half-activation voltage of KCNQ2/Q3 channels was increased,the activation curve shifted to the depolarized potentials,and KCNQ2/Q3 channel Ⅰ-Ⅴ curve slope was decreased in 10 mmol/L chloroprocaine group （P ＜ 0.05）.Conclusion Chloroprocaine concentration-dependently sup

关 键 词：KCNQ2钾通道 KCNQ3钾通道 麻醉药 局部 药物毒性 

分 类 号：R965[医药卫生—药理学]