β_1肾上腺素能受体抗体对小鼠心室肌细胞钾离子通道的作用  

Effect of the β_1-adrenoceptor antibody on potassium channels in mouse cardiac myocytes

作　　者：宋令岗[1] 李晓东[2] 马志勇[1] 王媛媛[1] 王建春[2] 黎莉[1] 

机构地区：[1]山东大学心血管重构和功能研究教育部和卫生部重点实验室,济南250012 [2]山东大学附属省立医院老年病科,济南250021

出　　处：《山东大学学报（医学版）》2011年第2期58-61,66,共5页Journal of Shandong University:Health Sciences

基　　金：山东省中青年科学家科研奖励基金(2006BS03051);山东省科技攻关计划基金(2009GG10002034);济南市科技专项基金(200705101-20)

摘　　要：目的采用β1肾上腺素能受体抗体(anti-ADRβ1)模拟自身抗体,研究其对小鼠心室肌细胞钾离子通道的作用。方法酶解法分离小鼠心室肌细胞,以不同稀释比例anti-ADRβ1灌流心肌细胞,膜片钳电生理技术记录钾离子通道电流的变化。结果不同稀释比例anti-ADRβ11/500、1/100、1/50的细胞外液灌流5min后,Ito电流密度无明显变化(P>0.05);与正常外液时(4.7±0.24)pA/pF比较,anti-ADRβ11/500时Iss电流密度(3.6±0.18)pA/pF降低,但差异无统计学意义(P>0.05),anti-ADRβ11/100和1/50时Iss电流密度明显降低,分别为(3.5±0.18)pA/pF和(3.1±0.15)pA/pF(P均<0.05),并且具有明显的剂量依赖性。结论β1肾上腺素能受体抗体可以抑制小鼠心肌细胞Iss通道而对Ito无影响,其作用可能类似激动剂样效应,该结论为进一步研究心衰患者β1肾上腺素能受体自身抗体的作用机制提供了实验依据。Objective：To investigate the influences of the adrenoceptor β1 antibody（anti-ADRβ1,simulating autoantibody） on potassium channels.Methods：Mouse ventricular cardiac myocytes were prepared by enzymatic isolating technique.The whole-cell patch-clamp technique was used to record K＋ currents,in which signals were amplified with an HEKA EPC-10 patch clamp amplifier and controlled by Pulse software.The voltage protocol was a one-second depolarizing pulse from-50 to ＋50 mV in 10 mV increments and at a holding potential of-60 mV.Cells were perfused with normal bath solution for 10 minutes to stabilize the currents,and then were perfused with anti-ADRβ1 in different concentrations（1/500,1/100 or 1/50） for 5 minutes.Changes of transient outward potassium channel（Ito） and steady state potassium channel（Iss） current intensity and corresponding current-voltage relationships were monitored.Results：After perfusing cardiac myocytes with anti-ADRβ1 in different concentrations for 5 minutes,current intensity and corresponding current-voltage relationships of Ito did not significantly chang（P0.05）.Compared with current intensity of Iss（4.7±0.24） pA/pF at normal bath solution,Iss（3.6±0.18） pA/pF decreased in 1/500 concentration of anti-ADRβ1 but without statistical significance,however,Iss significantly decreased in 1/100（3.5±0.18） pA/pF and 1/50（3.1±0.15） pA/pF concentrations of anti-ADRβ1 in an obvious dose-dependent manner.Conclusion：The aadrenoceptor β1 Antibody inhibits Iss potassium channels of mouse cardiac myocytes but not Ito,which may play a role by stimulating β1-adrenergic receptors.The results provide experimental basis for further investigation of the adrenoceptor β1 autoantibody in heart failure.

关 键 词：受体 β1肾上腺素能 抗体 钾离子通道 心肌细胞 小鼠 

分 类 号：R541.6[医药卫生—心血管疾病]