老龄心房颤动犬模型肺静脉肌袖细胞起搏电流在异丙肾上腺素作用下的变化  

Effect of isoproterenol on hyperpolarization activated cation current in elderly canine cardiomyocytes from pulmonary vein sleeves with atrial fibrillation

作　　者：蓝云锋[1] 文毅[1] 刘昱圻[1] 王红娟[1] 方舟[1] 高进辽[1] 李泱[1] 

机构地区：[1]解放军总医院老年心血管病研究所,北京市100853

出　　处：《中国组织工程研究与临床康复》2011年第15期2711-2715,共5页Journal of Clinical Rehabilitative Tissue Engineering Research

基　　金：国家自然基金面上项目(30570739)资助~~

摘　　要：背景:心房颤动是老年人常见的心律失常疾病,有研究表明肺静脉肌袖细胞起搏电流能增加快速心律失常特别是心房颤动发生的风险。目的:观察异丙肾上腺素对老龄犬肺静脉肌袖细胞起搏电流的作用。方法:选择14只老龄健康犬,7只快速起搏10周制备心房颤动模型,其余未经快速起搏处理的犬作对照。分离各组肺静脉肌袖细胞,利用全细胞膜片钳在电压钳模式下记录起搏电流。结果与结论:在0.1～10.0μmol/L的浓度范围内异丙肾上腺素均使细胞膜起搏电流电流升高,且作用呈现出浓度依赖性,半数有效量为1.7μmol/L(95%可信区间为1.2～2.6μmol/L)。房颤组肺静脉肌袖细胞给予1.0μmol/L异丙肾上腺素时,起搏电流显著增加,在-120mV的测试电位时,使其电流密度升高(P<0.01)。1.0μmol/L异丙肾上腺素使房颤组肺静脉肌袖细胞起搏电流的稳态激活曲线向正方向移动,使半激活电压下降,更接近静息电位,同时也使激活曲线斜率(P<0.01)。结果证实,异丙肾上腺素可能通过升高肺静脉肌袖细胞起搏电流促进心房颤动的发生。BACKGROUND：Atrial fibrillation is a common arrhythmia disease in the elderly,researches had shown that hyperpolarization activated cation current in pulmonary vein sleeve cardiomyocytes can increase the risk of arrhythmia such as atrial fibrillation.OBJECTIVE：To study effect of isoproterenol on hyperpolarization activated cation current in pulmonary vein sleeve cardiomyocytes of elderly canine with atrial fibrillation.METHODS：Fourteen healthy elderly canines,aged 7-9 years,were chosen,7 canines were subjected to long-term rapidly atrial pacing（10 weeks） to induce atrial fibrillation models,and the others served as control.Dissociation of pulmonary vein sleeve yielded single cardiomyocytes by using a Landengorff column without or with pacemaker activity from long-term rapid atrial pacing canines.Pace maker current was measured with the whole-cell patch-clamp technique.RESULT AND CONCLUSION：Isoproterenol increased the pace maker current in a concentration-dependent manner（0.1-10.0 μmol/L）.The median curative dose was 1.7 μmol/L（95% CI,1.2-2.6 μmol/L）.The isoproterenol（1.0 μmol/L） signIficantly increased pace maker current,and the current densities was increased at-120 mV test potential（P〈0.01）.Isoproterenol（10 μmol/L） caused an acceleration of current activation with V1/2 shIft to more positive potentials from mV,which approaching to rest membrane potential.Meanwhile,the slope of activated curve was changed（P〈0.01）.Our study revealed that isoproterenol signIficantly promote in pulmonary vein sleeve cardiomyocytes via increasing pace maker current.

关 键 词：异丙肾上腺素 老龄犬 心房颤动 肺静脉肌袖细胞 起搏电流 

分 类 号：R318[医药卫生—生物医学工程]