风湿性心脏瓣膜病患者钾离子通道特性变化的实验研究

目的:探讨风湿性心脏瓣膜病(简称风心病)患者心房组织细胞Kvl.5钾通道的变化。方法:将风心病患者分为窦性心律组(SR)、阵发性房颤组(PAF)和慢性房颤组(CAF)。应用全细胞膜片钳技术记录各组单个右心耳组织细胞超快速延迟整流钾电流(ultrarapid delayed rectifier current,IKur)的表达。结果:指令电压为+10~+50mV时,慢性房颤组(n=22)IKur密度较窦性心律组(n=25)明显降低。阵发性房颤组(n=23)IKur密度与窦性心律组差异无统计学意义(P>0.05);其中,在+50mV时,电流由窦性心律组(8.98+1.69)PA/pF降为房颤组的(4.17+1.82)PA/pF(P<0.01),降低幅度为(53.6+1.4)%。阵发性房颤组(8.21+1.54)PA/pF与窦性心律组差异无统计学意义(P>0.05),与慢性房颤组差异有统计学意义(P<0.01)。结论:Ikur密度在发生慢性房颤的风心患者心房肌细胞中密度明显下降,提示Kv1.5钾通道的变化与风心病房颤的发生有关。

Characteristic changes of potassium channel in rheumatic heart disease

Objective To explore Kv 1.5 potassium channels changes in the atrial tissue in patients with rheumatic heart disease.Method Patients with rheumatic heart disease were divided into sinus rhythm group（SR）,paroxysmal atrial fibrillation group（PAF）and chronic atrial fibrillation group（CAF）.Using whole-cell patch clamp technique in each group,the individual right atrial appendage tissue cells in the high-K solution,given before and after the ultra-fast delayed rectifier potassium current（ultrarapid delayed rectifier current,Ikur）changes.Results The command voltage was ＋10 ~ ＋50 mV,IKur density in CAF group（n= 22 cells）was significantly reduced than SR group（n=25 cells）.IKur density of PAF group（n= 23 cells）had no significant difference with SR group（P0.05）.In ＋50 mV,the current in SR group was（8.98±1.69）PA /pF,in AF group was（4.17±1.82）PA /pF（P0.01）,lower amplitude was（53.6±1.4）%.In PAF group was（8.21±1.54）PA /pF,had no significant difference with SR group（P0.05）,while had significant difference with CAF group（P0.01）.Conclusion Ikur density decreases obviously in atrial muscle cells of patients with chronic atrial fibrillation,suggesting that Kv 1.5 potassium channel changes is correlated with atrial fibrillation of rheumatic heart disease.