依折麦布和辛伐他汀对缺血再灌注大鼠心肌细胞瞬时外向钾电流的影响  

Effects of ezetimibe and simvastatin on transient outward potassium current in ischemiareperfused ventricular myocytes in rats

作　　者：张坤[1] 李广平[1] 李健[1] 程立君[1] 杨万松[1] 陈延勋 

机构地区：[1]天津医科大学第二医院心脏科,天津心血管病离子与分子机能重点实验室,天津心脏病学研究所,300211

出　　处：《天津医药》2015年第11期1296-1299,共4页Tianjin Medical Journal

摘　　要：目的研究依折麦布和辛伐他汀单独及联合使用对模拟缺血再灌注大鼠心肌细胞瞬时外向钾电流(Ito)的影响。方法将75只雄性SD大鼠按随机数字表法分为正常对照(CON)组、模拟缺血再灌注(CIR)组、依折麦布(EIR)组、辛伐他汀(SIR)组和依折麦布+辛伐他汀(ESIR)组,分别予生理盐水或其溶解的药物灌胃2周后分离右室心肌细胞,采用全细胞膜片钳技术记录Ito。结果 (1)Ito电流密度(+60 m V):CIR组较CON组下降,EIR组与CIR组比较差异无统计学意义(P>0.05),SIR组、ESIR组与CIR组比较均升高,SIR组与ESIR组比较差异无统计学意义(P>0.05)。(2)Ito稳态失活曲线最大半数失活电压(V1/2):CIR组较CON组显著增大,EIR组与CIR组比较差异无统计学意义(P>0.05),SIR组和ESIR组较CIR组均显著减小(P<0.05),SIR组和ESIR组比较差异无统计学意义(P>0.05)。斜率因子(K)各组间差异无统计学意义(P>0.05)。(3)失活后恢复曲线失活时间常数(τ)值:CIR组较CON组显著增加,EIR组与CIR组间差异无统计学意义(P>0.05),SIR组、ESIR组较CIR组明显减低(P<0.05),而SIR组与ESIR组比较差异无统计学意义(P>0.05)。结论辛伐他汀、依折麦布+辛伐他汀预处理可以逆转模拟缺血再灌注对心肌细胞Ito的影响,且效果相似,而依折麦布未表现出这种效果。Objective To observe the impact of alone or combined use of ezetimibe and simvastatin on transient outward potassium current （Ito） in ventricular myocytes of rat model of ischemia and reperfusion （IR）. Methods Seventy-five male SD rats were randomly divided into five groups, control group （CON）, control-IR group （CIR）, ezetimibe treatment group （EIR）, simvastatin treatment group （SIR） and combined ezetimibe and simvastatin treatment group （ESIR）. After two weeks of treat？ment with intragastic normal saline or drugs （ezetimibe or simvastatin）, myocytes were isolated from right ventricular with colla？genaseⅡ, and Ito was recorded by whole-cell patch clamp technique. Results （1） The Ito current density at＋60 mV was sig？nificantly decreased in CIR group than that of CON group （P〈0.05）. There was no significant difference in Ito current density between SIR group and ESIR group （P〉0.05）. The Ito current densities were higher in SIR group and ESIR group compared to those of CIR group. There was no significant difference in Ito current density between SIR group and ESIR group （P〉0.05）. （2） There was a significant increase in the half-inactivation （V1/2） in CIR group than that of CON group, but no significant differ？ence between EIR group and CIR group （P 〉0.05）. There was a significant difference in the half-inactivation （V1/2） in SIR group and ESIR group compared to that of CIR group （P〈0.05）, but no significant difference between SIR group and ESIR group （P〉0.05）. There was no significant difference in the slope factor （K） between five groups （P〉0.05）. （3） The time-con？stant （τ） of Ito recovery curves from inactivation was significantly higher in CIR group than that of CON group （P〈0.05）, which was no significant difference between EIR group and CIR group （P〉0.05）. There was a significant difference in the time-con？stant （τ） of Ito recovery curves from inactivation in SIR group and ESI

关 键 词：膜片钳术 再灌注损伤 依折麦布 辛伐他汀 瞬时外向钾电流 

分 类 号：R542.2[医药卫生—心血管疾病]