心功能不同的风湿性心脏瓣膜病心房颤动患者超极化激活环核苷酸门控阳离子通道4的表达水平研究

Expression Level of Hyperpolarization-activated Cyclic Nucleotide-gated Channel 4 in Patients With Atrial Fibrillation Associated With Rheumatic Valvular Heart Disease of Different Cardiac Functions

目的：探讨超极化激活环核苷酸门控阳离子通道4（HCN4）基因在风湿性心脏瓣膜病心房颤动伴心力衰竭患者与心功能正常的风湿性心脏瓣膜病心房颤动患者心房肌中的表达水平。方法选取2008—2011年新疆医科大学第一附属医院因心脏瓣膜病需接受开胸换瓣手术患者45例，根据其心功能分级，将美国纽约心脏病协会（ NYHA）分级为Ⅱ~Ⅲ级者27例作为试验组，将心功能正常者18例作为对照组。采用实时荧光定量PCR（ Real-time PCR）和蛋白质免疫印迹法（ Western-blotting）分别测定两组患者HCN4 mRNA及蛋白表达水平。结果对照组HCN4 mRNA表达水平为（1.12±0.69），低于试验组的（4.91±1.51）（t =0.021，P 〈0.05）。对照组 HCN4蛋白表达水平为（1.02±0.15），低于试验组的（2.01±0.92）（t=0.031，P〈0.001）。结论 HCN4在心力衰竭与心功能正常的风湿性心脏瓣膜病心房颤动患者的心房肌中均有表达，且随着心功能不全的加重，HCN4表达水平上调。

Objective To investigate the expression level of hyperpolarization -activated cyclic nucleotide -gated channel 4（HCN4）in the atrial muscle of patients with atrial fibrillation associated with rheumatic valvular heart disease with heart failure or normal cardiac function. Methods We enrolled 45 patients with valvular heart disease who were going to receive thoracotomy for valve replacement in the First Affiliated Hospital of Xinjiang medical University from 2008 to 2011. According to cardiac functional grading,we assigned 27 patients who were at grade Ⅱ-Ⅲin NYHA grading into trial group and assigned 18 patients with normal cardiac function as control group. Real -time PCR and Western -blotting were employed to determine mRNA level and protein expression level of HCN4 of the two groups. Results The mRNA expression level of HCN4 in control group was（1. 12 ±0. 69）,lower than that of trial group which was（4. 91 ± 1. 51） （t =0. 021,P 〈0. 05）. The protein expression level of HCN4 was（1. 02 ± 0. 15）,lower than that of trial group which was（2. 01 ± 0. 92） （t =0. 031,P 〈0. 001）. Conclusion There is HCN4 expression in the atrial muscle of patients with atrial fibrillation associated with rheumatic valvular heart disease. With the aggravation of heart failure,the expression level of HCN4 increases.