比索洛尔对心肌梗死后心室肌细胞动作电位时程及钾电流的影响  

The effect of bisoprolol on action potential duration (APD) and K^+ current in ventricular myocytes after myocardial infarction

作　　者：刘兵[1] 张荣庆[1] 王海昌[1] 郭文怡[1] 程何祥[1] 李飞[1] 张殿新[1] 秦涛[1] 徐凯[1] 张金霞[1] 贾国良[1] 

机构地区：[1]第四军医大学西京医院心内科,西安710032

出　　处：《解放军医学杂志》2005年第5期369-370,共2页Medical Journal of Chinese People's Liberation Army

摘　　要：目的观察心肌梗死(MI)后3周心室肌细胞动作电位时程(APD)及外向性电流的瞬时外向K+电流(Ito)和内向整流性K+电流(IK1)的改变,并探讨比索洛尔的保护作用。方法建立家兔MI模型,将动物随机分为3组:心肌梗死组(MI组)21只;用药组(βB组)20只;伪手术组(Sham组)20只。微电极记录APD;采用Langendoff灌流法获得单个心室肌细胞,利用膜片钳技术全细胞记录模式记录心室肌细胞Ito和IK1。结果非梗死区心室肌细胞的APD50、APD90MI组显著长于Sham组(P<0.05),βB组与Sham组比较差异无显著性。Ito电流密度MI组显著低于Sham组(6.46±2.91vs13.02±4.07,P<0.05),βB组(10.75±2.38)与Sham组比较差异无显著性。3组间IK1电流密度差异无显著性。结论比索洛尔可减轻MI非梗死区心室肌细胞APD及心室肌细胞Ito的变化,但对IK1电流密度无显著影响。Objective To investigate the changes of action potential duration (APD) and transient outward K + current (I to) and inward rectifier K + current(I K1) of ventricular myocytes after 3 weeks of myocardial infarction, and to inquire into the effect of bisoprolol. Methods APD was recorded with microelectrode. Ventricular myocytes were singly isolated from rabbit heart using modified Langendoff perfusion and soaked with collagenase. I to and I K1 of single rabbit ventricular myocytes were recorded by whole-cell path-clamp technique. Results Both APD 50 and APD 90 of the cell from noninfarcted region in MI group were markedly longer than that in sham group (P<0.05). There was no significant difference between Sham group and β-B group. The density of I to in MI group was lower than that in Sham group (6.46±2.91 vs 13.02±4.07, P<0.05). The density of I to in β-B group (10.75±2.38) was higher than that in MI group (P<0.05). There was no significant difference between β-B group and Sham group. The density of I K1 in MI group was lower than that in Sham group, but no significant difference was found among the three groups. Conclusion Bisoprolol may reduce the change of APD and the density of I to of ventricular myocytes from noninfarcted region, but has no significant effect on the density of I k1.

关 键 词：心肌梗死 动作电位时程 瞬时外向K^+电流 内向整流性K^+电流 比索洛尔 

分 类 号：R542.22[医药卫生—心血管疾病]