慢性房颤对风湿性心脏病心房肌细胞ELK-1、p-ELK-1表达的影响

Effects of chronic atrial fibrillation on expressions of ELK-1 and p-ELK-1 in atrial myocytes from rheumatic heart disease patients

目的研究风湿性心脏病慢性房颤患者心房肌细胞ELK-1、p-ELK-1的表达,探讨房颤发生与ELK-1、p-ELK-1表达之间的关系。方法12例风心病换瓣患者分为2组:①慢性房颤组(6例)房颤持续时间均>6个月,②窦性心律组(6例)为正常心律。手术中切取少许右心房游离壁组织采用免疫组化和间接免疫荧光技术检测心房肌ELK-1、p-ELK-1的表达与分布。结果①免疫组化显示ELK-1主要表达在心房肌细胞质和细胞核,慢性房颤心房肌较窦性心律心房肌表达明显减弱;②间接免疫荧光技术显示ELK-1在窦性心律心房肌细胞核表达相对较高,在房颤心房肌细胞核中表达明显受到抑制;p-ELK-1在房颤心房肌、窦性心律心房肌均表达受抑。结论转录激活因子ELK-1的表达改变可能在慢性房颤心房肌的分子重构中起着重要的作用。

Objective To investigate the influence of chronic atrial fibrillation （CAF） on ELK-1 and p- ELK-1 in the atrial myocytes from the rheumatic heart disease patients. Methods Right atrial myocardium was obtained from 12 patients undergoing valve replacement, 6 patients with CAF more than 6 months and 6 patients with sinus rhythm （SR）. The expressions of the ELK-1 and p-ELK-1 were examined by immunohistochemical staining and indirect immunofluorescence. Results Immunohistochemistry showed that the protein expression of ELK-1 was significantly reduced in atrial tissue of CAF patients as compared to that in SR patients, and immunostaining was mainly in both cytoplasm and nuclei of atrial myocardium. Indirect immunofluorescence against ELK-1 showed that the nuclei of SR cells were densely labeled, whereas nuclei in CAF cells were very faintly labeled. Indirect immunofluorescence against p-ELK-1 showed the nuclei in CAF cells and SR1 cells were all very faintly labeled. Conclusion Our results suggest that the expression change of transcriptional activator ELK-1 might play an important role in the pathogenesis of atrial fibrillation.