慢性房颤患者心房肌L型钙通道α1c亚基mRNA表达的观察

L-type Ca^(2+)-channel alpha 1c subunit mRNAs in atrial tissue of chronic AF patients

目的比较慢性房颤与窦性心律心房肌L型钙通道α1 c亚基mRNA的表达改变,探讨房颤心房肌L型钙通道的离子重构特点。方法选择43例接受心脏瓣膜置换的风心病患者,慢性房颤者24例,窦性心律者19例,于体外循环建立初采集右心房游离壁组织,应用半定量RT-PCR测定α1 c亚基Ⅰ-Ⅱ跨膜区连接对应的mRNA片段表达。结果慢性房颤心房肌L型钙通道α1 c亚基mRNA的表达较窦性心律心房肌无明显差异。结论房颤心房肌L型钙通道的离子重构可能与α1 c亚基的亚型表达改变有关。

Objective To detect the mRNA expression of L-type Ca^2＋ -channel α1c subunits in atrial myocardium and to further investigate the molecular mechanisms of electrical remodeling of chronic atrial fibrillation （AF）. Methods Right atrial tissue was obtained from 24 patients with chronic AF and 19 controls of sinus rhythm. All patients underwent valve replacement. Total RNA was isolated and reversely transcribed into cDNA. The cDNA of interest and of glyceraldehyde-3-phosphate dehydrogenase were amplified by semi-quantitative PCR and separated by ethidium bromide-stained gel electrophoresis. Results The mRNA expression of L-type Ca^2＋ -channel α1c subunits in chronic AF patients was of no significant difference with that of controls. Conclusion The gene expression of the L-type Ca^2＋ -channel subunits α1c is not reduced in atrial myocardium of AF patients. Therefore, the reduced α1c. L might be due to down-regulation of the splice isoforms of α1c subunits or other accessory subunits.