风湿性心房颤动患者左心房组织中钙蛋白酶-2的表达

Expression of calpain-2 in human left atrium in rheumatic atrial fibrillation

目的观察风湿性心房颤动(AF)患者左心房中钙蛋白酶-2(calpain-2)的表达,探讨其在AF发病机制中的作用。方法选取外科换瓣手术的风湿性心脏病患者39例,分为窦性心律组(n=16例)和心房颤动组(n=23例)。应用RT-PCR技术和免疫组化LSAB法半定量检测calpain-2的表达。结果心房颤动组calpain-2 mRNA的deltaCt值高于窦性心律组[(0.091±0.035)vs(0.066±0.022),P=0.017];两组左心房心肌细胞中均有棕黄色颗粒沉着,心外膜和心内膜细胞均未见棕黄色颗粒;心房颤动组中calpain-2表达含量明显高于窦性心律组(P<0.001),两者平均光密度值分别为0.92±0.17和0.65±0.01;calpain-2的含量与左心房收缩末期直径呈正相关(r=0.929,P<0.001)。结论 calpain-2在人类左心房心肌细胞中表达;AF时calpain-2的表达明显增加。

Objective To observe the expression of calpain-2 in the left atrum of patients with rheumatic atrial fibrilla-tion, and to explore its roles in the pathogenesis of atrial fibrillation.Methods A total of 39 patients with rheumatic heart disease who received surgical valve replacement were divided into two groups： the atrial fibrillation group （ n=23） and sinus rhythm group （n=16）.The expression of calpain-2 was detected with LSAB immunohistochemical and the Real-time PCR technology.Results The deltaCt of calpain-2 mRNA of the atrial fibrillation group （ 0.091 ± 0.035） was higher than that of the sinus rhythm group （0.066 ±0.022, P=0.017）.Brown particle deposits were ob-served in the left atrial myocytes in both groups, but the epicardial and endocardial cells showed no brown particles.The average optical density values of calpain-2 of the atrial fibrillation group and sinus rhythm group were （0.92 ±0.17） and （0.65 ±0.01）（P＆lt;0.001）.Calpain-2 levels and left atrial systolic diameter were correlated （r=0.929, P＆lt;0.01）.Conclusion Calpain-2 exists in the left atrial myocytes.The expression of calpain-2 increases significantly in case of atrial fibrillation.