【摘要】 目的研究慢性房颤(AF)患者心房肌细胞乙酰胆碱敏感钾通道(KAch)Kir3.4基因及蛋白表达变化,探讨其在AF离子通道重构机制中的作用。方法选择22例心脏瓣膜病手术患者,根据基础心律分为AF组9例和窦性心律(SR)组13例。术中AF组取左、右心房标本,SR组取右心房标本,用半定量RT-PCR技术检测心房肌细胞KAch基因Kir3.4 mRNA表达,蛋白免疫印迹法检测Kir3.4表达的KAch蛋白亚基GIRK4表达。结果与SR组比较,AF组心房肌细胞Kir3.4 mRNA表达明显减少,GIRK4蛋白表达明显降低(P均<0.05)。AF组左、右心房肌细胞Kir3.4 mRNA表达及GIRK4蛋白含量无统计学差异(P>0.05)。结论慢性AF患者心房肌细胞KAch通道的Kir3.4基因及蛋白表达均下调,此变化可能是KAch通道电流密度减小的分子基础,是机体代偿保护机制反应。更多还原

【Abstract】 Objective To study the expression of gene and protein of Kir3.4 of acetylcholine sensitive K+channel(KAch) in human atrial myocytes of the patients with chronic atrial fibrillation(AF) and to reveal the role of the expression underlying channel remodeling in chronic AF.Methods Twenty-two patients with cardiac valve disease were divided into AF group(n=9) and sinus rhythm(SR) group(n=13) according to basic rhythm.Right and left atrial appendages were obtained in AF group underwent cardiac valve replacement surgery,and right atrial appendages were obtained as controls in SR group.The mRNA expression of Kir3.4 of the KAch in atrial myocytes was detected with reverse transcription polymerase chain reaction(RT-PCR),the protein GIRK4 expression of Kir3.4 was measured with Western Blot.Results The mRNA and the protein GIRK4 expression level of Kir3.4 of the KAch were both significantly lower in AF group than in SR group(P<0.05),while no significant difference was found in the mRNA and the protein of GIRK4 expression between left and right atrial tissue in the AF group.Conclusion The gene and protein expression of Kir3.4 of KAch decrease in chronic AF,which possibly contribute to molecular basis of the decrease of current density of KAch,and may indicate a compensatory response of body.更多还原