窦性心律与心房颤动患者心房成纤维细胞大电导钙激活钾通道表达差异研究

Differential expression of BKCa channels in atrial fibroblasts in patients with sinus rhythm and atrial fibrillation

目的通过分析窦性心律与心房颤动患者心房肌成纤维细胞BKCa通道表达差异,探索心肌纤维化产生的机制,为治疗和逆转心房颤动结构重构提供新的治疗策略。方法选择西南医科大学附属医院心胸外科2015年6月至2016年12月收治确诊为风湿性心脏病且行体外循环瓣膜置换术的10例患者,其中窦性心律患者(窦性心律组)5例,男2例、女3例,年龄(49.1±8.3)岁;心房颤动患者(心房颤动组)5例,男3例、女2例,年龄(50.3±5.8)岁。于术中获取右心耳组织约100 mg,采用组织块贴壁法培养心房成纤维细胞,实时荧光定量聚合酶链式反应(q RT-PCR)检测培养的成纤维细胞中BKCa通道m RNA表达水平及western blotting检测BKCa通道蛋白的表达情况。结果 (1)比较心房颤动组及窦性心率组患者的一般情况,两组患者年龄(t=1.21,P=0.67)、性别(t=2.56,P=0.75)差异无统计学意义。两组患者左房内径、右房内径差异有统计学意义(t=19.45,P=0.01;t=23.52,P=0.06)。(2)两组BKCaα和BKCaβ1的m RNA表达差异无统计学意义(t=3.14,P=0.79;t=2.88,P=0.69);(3)两组BKCaα和BKCaβ1的蛋白表达差异均无统计学意义(t=0.55,P=0.31;t=0.73,P=0.46)。结论 BKCa通道可能不参与心房颤动的发生及维持,其在心肌纤维化进程中可能发挥着作用。

Objective Through analyzing BKCa channel expression in atrial fibroblasts in patients with sinus rhythm and atrial fibrillation （AF）, to explore the mechanism of myocardial fibrosis and provide new therapeutic strategies for the treatment and reversal of AF structure reconstruction. Methods We selected 10 patients of rheumatic heart valvular disease who underwent valve replacement surgery. They were 5 patients with sinus rhythm （a sinus rhythm group, 2 males and 3 females with an average age of 49.1±8.3 years） and 5 with AF （an AF group, 3 males and 2 females with an average age of 50.3±5.8 years）. About 100 mg tissue was obtained from the right auricula dextra, and the atrial fibroblasts were cultured by tissue block adherence method, and the expression of BKCa channel genes and proteins in cultured fibroblasts was detected by quantitative real-time polymerase chain reaction （qRT-PCR） and western blotting methods. Results （1） The general data of 10 patients between the AF group and the sinus rhythm group were compared. There was no significant difference between the two groups in age （t=1.21, P=0.67） and sex （t=2.56, P=0.75）. There was statistical difference in the left atrial diameter and the right atrium diameter between the two groups （t=19.45, P=0.01; t=23.52, P=0.06）; （2） the mRNA expression of BKCa subunit was detected by qRT-PCR method, and there was no significant difference in the mRNA expression of BKCa ct and BKCa β1 between the two groups （t=3.14, P=0.79; t=2.88,P=0.69）; （3） the expression of BKCa protein was detected by western blotting method, and there was no significant difference in the protein expression of BKCa a and BKCa β1 between the two groups （t=0.55, P=0.31; t=0.73, P=0.46）. Conclusion BKCa pathway may not be involved in the pathogenesis and maintenance of AF, but it may play an important role in the process of myocardial fibrosis.