李惠,高鸿,赵艳,安丽,刘艳秋,龙娟,张凯强
LI Hui,GAO Hong,ZHAO Yan,AN Li,LIU Yanqiu,LONG Juan,ZHANG Kaiqiang

• 1:贵州医科大学麻醉学院
• 2:贵州医科大学附院麻醉科
• 3:贵阳市第一人民医院麻醉科

摘要(Abstract)：

目的:探讨低温联合右美托咪定对心室复极时程和CX43蛋白表达的影响。方法:成年家兔制备Langendorff离体心脏灌注模型,取模型制备成功的心脏18个,随机均分为正常对照组(C组)、低温组(H组)、低温联合右美托咪定组(HD组),C组继续灌注37℃K-H液60 min,H组灌注32℃K-H液60 min,HD组灌注32℃含25μg/L右美托咪定的K-H液60 min;于平衡灌注末(T0)、灌注K-H液15(T_1)、30(T_2)和60 min(T_3)时记录心率和3层心肌单相动作电位,测量单相动作电位复极50%时程(MAPD_(50))和单相动作电位复极90%时程(MAPD_(90)),记录完毕后取左心室前壁心肌组织进行western blot检测CX43蛋白表达。结果:与C组T0时点比较,H组及HD组T1-3时HR减慢,心肌MAPD_(50)和MAPD_(90)延长(P<0.05);与C组比较,H组及HD组T1-3时HR减慢,心肌MAPD_(50)和MAPD_(90)延长(P<0.05);与C组比较,H组和HD组CX43蛋白表达明显降低(P<0.05)。结论:CX43蛋白的表达下降可能是低温造成心室复极不均一性增大的原因,而右美托咪定既不影响CX43蛋白表达,也不加重低温对心室复极时程的的影响。
Objective:To evaluate the effect of hypothermia combined with dexmedetomidine( DEX)on duration of ventricle repolarization and the expression of CX43. Methods:Eighteen Langendorff perfused heart models were prepared from adult New Zealand white rabbits,and randomly divided into3 groups( n = 6) :control group( group C),hypothermia group( group H),and hypothermia plus DEX group( group HD). Continuous perfusion was conducted for 60 mins to different groups with different solutions:37℃ Krebs-Henseleit( K-H) solution for group C,32 ℃ K-H for group H,and 32℃K-H plus DEX at 25 ng/ml for group HD. The heart rate and 3-layer myocardial monophasic action potential( MAP) of left ventricular anterior wall were recorded immediately after perfusion balanced( T_0) and in 15 min( T_1),30 min( T_2),and 60 min( T_3) after perfusion balanced were recorded.The durations of repolarization at 50%( MAPD50),and 90%( MAPD90) were tested. Finally,sections of the left anterior ventricular wall were taken and CX43 protein expression was detected with Western blot. Results:Compared with group C,group H and group HD showed longer MAPD_(50),and MAPD_(90) and decreased protein expression of CX43( P < 0. 05),and there was no statistically significant difference between groups H and HD( P > 0. 05). Conclusion:The decreased expression of CX43 might be the reason for extension of the duration of repolarization caused by hypothermia.Dexmedetomidine has no influence on CX43 expression,or effect of hypothermia.

关键词(KeyWords)： 连接蛋白43;低温;右美托咪定;心脏跨室壁复极离散度;兔
connexin 43;hypothermia;dexmedetomidine;ventricular repolarization dispersion;rabbits

Abstract:

Keywords:

基金项目(Foundation): 贵州省科技厅联合基金项目[黔科合LH字(2016)7252号];; 贵州省大学生创新创业训练计划项目(201510660022)

作者(Author): 李惠,高鸿,赵艳,安丽,刘艳秋,龙娟,张凯强
LI Hui,GAO Hong,ZHAO Yan,AN Li,LIU Yanqiu,LONG Juan,ZHANG Kaiqiang

DOI: 10.19367/j.cnki.1000-2707.2017.03.006

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