Henan Medical Key Laboratory of Arrhythmia, Zhengzhou No. 7 People's Hospital, Zhengzhou, Henan, China.
Department of Cardiac Surgery, Zhengzhou No. 7 People's Hospital, Zhengzhou, Henan, China.
Cell Biol Int. 2022 Nov;46(11):1834-1840. doi: 10.1002/cbin.11864. Epub 2022 Jul 23.
The objective of the study was to investigate the expression levels of potassium voltage-gated channel subfamily A member 5 (KCNA5), connexin 43 (Cx43), and connexin 40 (Cx40) in the left atrial appendage of patients with atrial fibrillation (AF) and the interactions between them. We gathered tissue samples from patients with persistent AF and sinus rhythm and used fluorescence quantitative polymerase chain reaction to evaluate messenger RNA (mRNA) changes of KCNA5, Cx43, and Cx40. Then, we studied the protein levels of KCNA5, Cx43, and Cx40 by immunofluorescence and western blot analysis and the interactions between these proteins were identified by immunoprecipitation and immunofluorescence colocation, respectively. Compared with the control group, the mRNA and protein levels of KCNA5, Cx43, and Cx40 in the AF group were decreased and the positive expression of KCNA5, Cx43, and Cx40 protein was also decreased by immunofluorescence staining in the AF group. In addition, immunoprecipitation and immunofluorescence colocation revealed that KCNA5 was coexpressed with Cx43 and Cx40 proteins. The expressions of KCNA5, Cx43, and Cx40 were substantially downregulated in the myocardium of patients with AF and KCNA5 interacted with Cx43 and Cx40 proteins, respectively.
本研究旨在探讨钾电压门控通道亚家族 A 成员 5（KCNA5）、连接蛋白 43（Cx43）和连接蛋白 40（Cx40）在心房颤动（AF）患者左心耳中的表达水平及其相互作用。我们收集了持续性 AF 和窦性节律患者的组织样本，并用荧光定量聚合酶链反应评估 KCNA5、Cx43 和 Cx40 的信使 RNA（mRNA）变化。然后，我们通过免疫荧光和 Western blot 分析研究了 KCNA5、Cx43 和 Cx40 的蛋白水平，并通过免疫沉淀和免疫荧光共定位分别鉴定了这些蛋白之间的相互作用。与对照组相比，AF 组 KCNA5、Cx43 和 Cx40 的 mRNA 和蛋白水平均降低，且 AF 组 KCNA5、Cx43 和 Cx40 蛋白的阳性表达也通过免疫荧光染色降低。此外，免疫沉淀和免疫荧光共定位显示 KCNA5 与 Cx43 和 Cx40 蛋白共表达。AF 患者心肌中 KCNA5、Cx43 和 Cx40 的表达均显著下调，KCNA5 分别与 Cx43 和 Cx40 蛋白相互作用。
