摘要
目的 研究心房颤动 (房颤 )患者心房组织钾通道Kir2 1和Kir3 4基因表达的改变。方法 将 4 6例风湿性心瓣膜病接受换瓣手术患者分为 3组 ,窦性心律 (SR)组 18例 ,阵发性房颤 (PAF)组7例 ,慢性房颤 (CAF)组 2 1例 ,应用半定量逆转录 聚合酶链反应 (RT PCR)技术 ,检测心房组织Kir2 1、Kir3 4mRNA表达。结果 和SR组相比 ,Kir2 1mRNA在CAF组中的表达增加具有显著性 (P <0 0 1) ;Kir3 4mRNA在PAF组 (P <0 0 5 )和CAF组 (P <0 0 1)中的表达均显著减少。结论 风湿性心瓣膜病伴房颤患者Kir2 1mRNA表达上调和Kir3 4mRNA表达下调 ,可能分别是IK1 上调、IKACh下调的分子基础 ,Kir3 4mRNA表达水平的减少可能是机体为拮抗房颤电重构时有效不应期缩短的代偿机制之一。
Objective To investigate whether patients with atrial fibrillation (AF) show alterations in Kir2.1 and Kir3.4 potassium channel gene expression.Methods Right atrial appendages were obtained from 7 patients with paroxysmal AF(PAF group),21 patients with chronic AF(CAF group) and 18 patients matched controls in sinus rhythm(SR group).All patients underwent cardiac valve replacement surgery.Total RNA was isolated and reversely transcribed into cDNA.In a semi-quantitative polymerase chain reaction the cDNA of interest and of glyceraldehydes-3-phosphate dehydrogenase were coamplified and separated by ethidium bromide stained gel-electrophoresis.Results Compared with patients in SR group,mRNA levels of Kir2.1 increased in patients with CAF[(0.38±0.24)vs(0.62±0.23), P <0.01],mRNA levels of Kir3.4 were reduced in patients with PAF and CAF[(0.56±0.25)vs(0.35±0.18), P <0.05;(0.56±0.25)vs(0.32±0.11), P <0.01].Conclusions The gene expression of Kir2.1 in atria of patients with AF increases but Kir3.4 decreases.Human atrial fibrillation induces transcriptionally mediated upregulation of I_ K_1 and downregulation of I_ KACh .Atrial myocytes adapt to AF by downregulating mRNA levels of Kir3.4 to counteract the shortening of the atrial effective refractory period due to electrical remodeling.
出处
《中华心律失常学杂志》
2003年第6期356-358,共3页
Chinese Journal of Cardiac Arrhythmias
