中文摘要：

目的：探讨心房颤动（房颤）患者心房肌乙酰胆碱兴奋钾电流（Ix，Ach）通道基因和蛋白表达变化，以了解Ik，Ach通道在房颤发生中的可能作用机制。方法：入选行心脏瓣膜病手术患者作研究对象，其中并发房颤者9例（房颤组），实性心律者13例（对照组）。所有入选患者于开胸行心脏手术时切取右心耳组织，房颤组患者同期加取左心耳组织。用RT—PCR和Western—Blot检测不同心房肌组织中人Kir3．4基因及蛋白水平的表达。结果：房颤组患者Ik，Ach通道蛋白mRNA表达水平及蛋白含量均较对照组患者减少（P〈0．05）。结论：Ik，Ach通道蛋白mRNA表达水平及蛋白含量较少可能是慢性房颤患者发病机制之一。

英文摘要：

Objective： To investigate the gene and protein expressions of Ik, Ach and reveal its underlying mechanism in Atrial fibrillation. Method： Right and left atrial appendages were obtained from 9 patients with chronic atrial fibrillation, and right atrial appendages from 13 patients were set as controls of sinus rhythm （SR） group, All patients underwent cardiac valve replacement surgery,the mRNA and protein expression level of Kir3.4 of the Ix ,Ach channel were detected with reverse transcription polymerase chain reaction （RT-PCR） and Western Blot. Result：The mRNA and protein expressions level of Kit3.4 of the IkAch channel are both much lower in AF group than in SR group , while no significant difference was found in left and right atrial tissue within the AF group itself. Conclusion：The decrease of GIRK4 of the Ik, Aeh channel in patients with AF is caused by the decreasing expression of the mRNA, and it maybe underlying the decrease of Ix, Ach, which may indicate a compensatory response of atrium to chronic atrial fibrillation.