[mRNA genomics change and significance of important ion channel proteins in patients with atrial fibrillation].

To investigate the mRNA genomics changes and significance of important ion channel proteins in patients with atrial fibrillation (AF), to reveal the mechanism of electrical remodeling in AF. Ninety patients with AF were chosen to receive the radiofrequency ablation (AF-RFA), 90 healthy subjects were included as the normal control group.The coronary sinus blood and peripheral venous blood were taken from each AF patient during the operation of AF-RFA.The genome-wide mRNA expression profile was analyzed with mRNA microarray chip, and the mRNA expression difference results for the major ion channel gene was further validated using Real-time PCR test. The expression of twelve ion channel protein mRNA increased ≥2.0-fold, expression of 10 mRNA decreased ≥2.0-fold, among which K(+) channel gene KCNE4, KCND2, KCNN4 declined obviously, KCNA5 dropped 11.54-fold (< 0.01); KCNS3, KCNS1, KCNG1, KCNG7 and Ca(+ +) channel gene CACNA2D3 increased significantly.Compared with autologous peripheral blood, 12 mRNAs of ion channel protein in coronary sinus blood of AF patients was differentially expressed ≥2.0-fold.Compared with control group in peripheral blood, 7 ion channel protein mRNA expression differences was ≥2.0-fold, and the KCNA5 gene expression was down by 8.13-fold.RT-PCR confirmed that the trend and extent of differential expression were consistent with the chip results.The results of myocardial tissue RT-PCR showed that CACNA1C, KCNC3, KCNG1 and KCNK7 mRNA were up-regulated in AF (<0.05), and other ion channel mRNA expressions were down-regulated (<0.05). KCNA5 was down-regulated most obvious. The down-regulation of KCNA5 gene expression in AF patients is most obvious, and more potassium ion channel expression differences are also significant, so that the potassium ion channel reconstruction may play a dominant or much more important role in AF electrical remodeling.