右心房组织中 M3受体及缝隙连接蛋白43与心房颤动的相关性研究

目的：探讨M3受体及Cx43在心房颤动发生与维持中的作用及二者之间的相互关系。方法收集94例风湿性心脏病瓣膜置换术患者右心房组织，按是否存在心房颤动分为心房颤动组（ AF组，49例）和窦性心律组（ SR组，45例），采用免疫荧光在激光共聚焦显微镜下观察M3受体和Cx43蛋白的表达及两者的结构共定位情况，采用Western blot方法检测两组M3受体和Cx43蛋白的蛋白表达量。结果与SR组相比，AF组心房组织M3受体及Cx43蛋白表达量下降（P＜0．05），但M3受体与Cx43的结构共定位关系增强（P＜0．05）。结论房颤患者右心房组织Cx43表达量下降，可能是房颤发生与维持机制之一，M3受体的表达量下降及其与Cx43的结构共定位关系增强，则可能是心房颤动时心肌细胞的自我保护、延缓电重构的机制。

Roles of M3 receptor and Cx43 in human atrial fibrillation

Objective To investigate the potential roles of M 3 receptor and connexin 43 （ Cx43 ） in the occurrence and maintenance of human atrial fibrillation （ AF） and the relationship between them .Methods The right atrial tissues were obtained from 94 patients with rheumatic heart disease undergoing cardiac surgery , and then were divided into group AF （n=49）, and sinus rhythm group （group SR, n=45）.The co-localization of M3 receptor and Cx43 was detected by immunofluorescence and confocal microscopy .The expression levels of M3 receptor and Cx43 protein were measured by Western blotting.Results Compared with group SR, the expression levels of M3 receptor and Cx43 protein were signifi-cantly down-regulated （P＆lt;0.05）, while the co-localization of M3 receptor and Cx43 were enhanced in the group AF （P＆lt;0.05）.Conclusions The down-regulation of Cx43 in the right atrial tissues of AF patients may be one of the mechanisms of occurrence and maintenance of AF , and the decrease of M3＆#39;s expression and increase of co-localization of M3 receptor and Cx43 may be the protective mechanisms of preventing atrial electrical remodeling produced by cardiomyocytes .