胡椒碱对H_2O_2致兔心房肌细胞动作电位时程及L型钙电流异常的保护作用  

Protective effect of piperine on abnormalities of action potential duration and L-type calcium current induced by hydrogen peroxide 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：《心脏杂志》2012年第2期141-145,共5页Chinese Heart Journal

基　　金：国家自然科学基金项目资助(30772886)

摘　　要：目的:研究胡椒碱(PIP)对H2O2引起的单个兔心房肌细胞动作电位时程(APD)及L型钙电流(ICa,L)异常的保护作用。方法:采用全细胞膜片钳技术,观察10和50μmol/L的H2O2引起单个兔心房肌细胞APD及ICa,L的改变,以及预先应用7μmol/L的PIP对其的作用。结果:7μmol/L的PIP对正常兔心房肌细胞APD、ICa,L及L型钙通道动力学无明显影响。在10和50μmol/L的H2O2作用下,兔心房肌细胞APD50和APD90明显缩短(P<0.05),静息膜电位(RMP)绝对值显著下降(P<0.05),ICa,L峰值由(39.3±5.4)pA/pF降低至(32.8±2.0)pA/pF(P<0.05),电流-电压曲线上移,通道稳态激活曲线右移,通道稳态失活曲线左移,但恢复时间不变。预先给予7μmol/L的PIP可明显减轻H2 O2对APD、ICa,L的抑制作用(P<0.01),对L型钙通道动力学的异常影响。结论:PIP可减轻氧化应激对心房肌细胞APD、ICa,L的影响。AIM： To study the protective effect of piperine on the abnormalities of action potential dura- tion and L-type calcium current （Ica,L） induced by hydrogen peroxide in single rabbit atrial myocyte. METHODS： Whole-cell patch clamp technique was used to study the effect of H2O2 （10 and 50 μmol/L） on APD and ICa,L in single rabbit atrial myocyte and the effect of pretreatment with piperine （7 μmol/L）. RESULTS： Piperine （7 μmol/L） had no significant effect on APD and Ica,L of normal single rabbit atrial myocyte as well as its channel dynamics. In the presence of 10 and 50 p, mol/L H2O2, APDs0 and APD90 decreased （P 〈 0. 05 ）, amplitude of RMP disincreased （ P 〈 0.05 ）, the peak of ICa,L was significantly reduced （P 〈0. 05）, I-V curve shifted upward, steady-state activation curve of ICa,L was shifted to positive potentials, and steady-state inactivation was shifted to negative potentials, but recovery from inactivation of ICa,L showed no remarkable changes. Piperine （7 μmol/L） significantly alleviated the inhibitory effect of H2O2 on APD and Ica,L （P 〈 0. 01 ） and protected the changes of ICa,L dynamics induced by H202. CONCLUSION： Piperine can alleviate abnormalities of APD and Ica,L induced by hydrogen peroxide in atrial myocytes.

关 键 词：胡椒碱 过氧化氢 氧化应激 动作电位时程 L型钙电流 

分 类 号：R282.71[医药卫生—中药学]