实用医学杂志2023，Vol.39Issue(21)：2750-2753,4.DOI:10.3969/j.issn.1006-5725.2023.21.010
低温缺血-再灌注对离体大鼠心房肌Kir2.1和CaMKⅡ表达的影响
Effect of hypothermic ischemia-reperfusion on the expression of Kir2.1 and CaMKⅡ in isolated rat atrial myocardium
摘要
Abstract
Objective To explore the molecular mechanism of prolonged atrial repolarization in rats with reperfusion atrial arrhythmia.Methods Sixteen Langendorff isolated heart perfusion models made by male SD rats were randomly divided into control group(group C,n = 8)and hypothermic ischemia-reperfusion group(group IR,n = 8).According to the occurrence of atrial arrhythmia after reperfusion,group IR was further subdivided into reperfusion non-atrial arrhythmia subgroup(group N-RAA)and reperfusion atrial arrhythmia subgroup(group R-AA).Group C was perfused with 37℃K-H solution for 120 min.In group IR,the isolated heart was perfused with 37℃K-H solution for 30 min and stopped,and the isolated heart was perfused with 4℃Thomas solution(20 mL/kg)for 60 mins.When the heart stopped for 30 mins,the isolated heart was perfused with a half dose of 4℃Thomas solution(10℃).During cardioplegia,the isolated heart was protected by low temperature Thomas solution(4℃),and then reperfused for 30 mins with 37℃K-H solution.The monophasic action potential(MAP)of the right atrium was recorded at balanced perfusion for 30 mins(T0),balanced perfusion for 105 mins in group C/reperfusion for 15 mins in group IR(T1)and balanced perfusion for 120 mins in group C/reperfusion for 30 min in group IR(T2);The duration of 50%and 90%repolarization of monophasic action potential(MAPD50 and MAPD90)was measured.After electrophysiological monitoring,the expression of Kir2.1 and CaMKⅡ in right atrium was detected by Western blot.Results Compared with T0,MAPD50 and MAPD90 at T1 and T2 were significantly prolonged in group R-AA(P<0.05),and MAPD90 at T1 and T2 in group R-NAA and group R-AA were significantly longer than those in group C(P<0.05).Compared with group R-NAA,MAPD50 and MAPD90 in group R-AA were significantly prolonged at T1 and T2(P<0.05).The results of Western blot showed that the expression of Kir2.1 in group R-NAA and group R-AA was significantly lower than that in group C(P<0.05),and that in group R-AA was significantly lower than that in group R-NAA(P<0.05).The expression of CaMKⅡ in group R-NAA and group R-AA was significantly higher than that in group C(P<0.05),and the expression of CaMKⅡ in group R-AA was significantly higher than that in group R-NAA.Conclusion The prolonged duration of atrial repolarization in rats with hypothermic ischemia-reperfusion atrial arrhythmia may be related to the down-regulation of Kir2.1 expression and the up-regulation of CaMKⅡ expression.关键词
缺血-再灌注/心房肌/复极时程/内向整流钾通道2.1/Ca2+/CaM依赖激酶ⅡKey words
ischemia-reperfusion/atrial myocardium/duration of repolarization/inwardly rectifying K channels 2.1/Ca2+-calmodulin kinase Ⅱ分类
医药卫生引用本文复制引用
何幼芹,高鸿,种朋贵,刘艳秋,佟睿,吴学艳..低温缺血-再灌注对离体大鼠心房肌Kir2.1和CaMKⅡ表达的影响[J].实用医学杂志,2023,39(21):2750-2753,4.基金项目
贵州省卫生健康委科学技术基金项目(编号:gzwkj2021-270) （编号:gzwkj2021-270）
