胡椒碱对H_2O_2所致兔心房肌细胞瞬时外向钾电流异常的保护作用  

Protective effect of piperine on H_2O_2-induced abnormal transient outward potassium current in rabbit atrial myocytes

作　　者：刘岩[1] 李泱[2] 林琨[1] 田苗[1] 王玉堂[1] 单兆亮[1] 

机构地区：[1]解放军总医院心内科,北京100853 [2]解放军总医院老年心血管病研究所,北京100853

出　　处：《军医进修学院学报》2012年第5期496-499,共4页Academic Journal of Pla Postgraduate Medical School

基　　金：国家自然科学基金项目(30772886)~~

摘　　要：目的研究胡椒碱对H2O2引起的兔单个心房肌细胞瞬时外向钾电流(Ito)异常的保护作用。方法采用全细胞膜片钳技术分析50μmol/L的H2O2对兔单个心房肌细胞Ito的影响,并研究预先应用7μmol/L的胡椒碱对其的保护作用。结果 7μmol/L胡椒碱对正常兔心房肌细胞Ito及其通道动力学无显著影响。在50μmol/L H2O2作用下,兔心房肌细胞Ito峰值由(39.3±5.4)pA/pF降低至(32.8±2.0)pA/pF(P<0.05),电流-电压曲线下移,通道稳态激活曲线右移,通道稳态失活曲线及恢复时间不变,关闭态失活加速。预先给予7μmol/L胡椒碱,明显减轻H2O2对Ito的抑制作用(P<0.01),并可减轻H2O2对瞬时外向钾通道动力学的异常影响。结论胡椒碱可减轻氧化应激对心房肌细胞Ito的影响。Objective To study the protective effect of piperine on H2O2-induced abnormal transient outward potassium current（Ito） in single rabbit atrial myocyte. Methods Effect of H202（50 μ mol/L） and piperine（7 μ mol/L） on Ito in single rabbit atrial myocyte was analyzed using the whole cell patch clamp technique. Results Piperine（7 μ mol/L） had no significant effect on Ito and its transient outward potassium channel dynamics. The peak value of Ito in rabbit atrial myocytes decreased to （32.8 ± 2.0）pA/pF from （39.3 ± 5.4） pA/pF（P〈0.05）, the current-voltage curve of Ito was shifted down, the channel steady-state activation curve of Ito was shifted to the right, the steady-state inactivation curve and the recovery time of Ito from inactivation did not change, the closed-state inactivation of Ito was accelerated, when H2O2（50 μ mol/L） was applied. Piperine（7 μ mol/L） significantly alleviated the inhibitory effect of H2O2 on Ito and its transient outward potassium channel dynamics（P〈0.01）. Conclusion Piperine can alleviate H2O2-induced abnormal Ito in rabbit atrial mvocvtes.

关 键 词：胡椒碱 过氧化氢 瞬时外向钾电流 

分 类 号：R349.5[医药卫生—基础医学]