心房颤动患者心房肌钙平衡调节蛋白基因的mRNA表达的研究

Gene expression of proteins influencing the calcium homeostasis in patients with atrial fibrillation

目的 通过对临床患者的心房肌钙平衡调节蛋白的mRNA表达水平的测定 ,揭示心房颤动 (房颤 )的发生机制。方法 采集风湿性心脏病窦性心律 (窦律 )组患者 (12例 )和房颤组患者 (12例 )的右心耳组织 ,应用逆转录 聚合酶链反应技术以GAPDH为内参照 ,测定心房肌钙平衡调节蛋白mRNA表达水平。结果 与窦律组相比 ,房颤组细胞膜L型钙通道的mRNA表达减低 44 6 2 % (0 2 5±0 16与 0 13± 0 13,P <0 0 5 ) ,肌浆网钙泵mRNA表达水平降低 2 6 2 2 % (0 38± 0 14与 0 2 8± 0 14,P<0 0 5 ) ,而磷酸受纳蛋白、ryanodine受体和细胞膜钠 钙交换的mRNA表达水平差异无显著性。结论房颤患者心房肌细胞膜L型钙通道和肌浆网钙泵mRNA表达水平降低 ,提示细胞内钙超载机制参与了房颤发生和维持。

Objective To study the molecular mechanisms of atrial fibrillation by measuring the gene expression of proteins influencing the calcium homeostasis. Methods Right atrial appendages were obtained from 12 patients with atrial fibrillation (cases) and from 12 matched controls with sinus rhythm. The mRNA expression of proteins influencing the calcium homeostasis was measured by reverse transcription-polymerase chain reaction and normalized to the mRNA level of glyceraldehyde-3-phosphate dehydrogenase. Results Compared to controls the mRNA level of L-type calcium channel in patients with atrial fibrillation reduced by 44.62%( P <0.05) and sarcoplasmic reticulum calcium ATPase mRNA decreased by 26.22%( P <0.05). No changes in mRNA expression of Na +-Ca 2+ exchanger, phospholamban and ryanodine receptor type 2 were observed between cases and controls. Conclusion The gene expression of L-type calcium channel and sarcoplasmic reticulum calcium ATPase are down-regulated in atrial fibrillation patients, suggesting that calcium loading may be responsible for the occurrence and maintenance of atrial fibrillation.