二十二碳六烯酸对心房颤动大鼠心房肌生理改变及双孔钾通道TASK-1蛋白表达的影响  

Effects of docosahexaenoic acid on atrial physiological parameter and TASK-1 protein expression in atrial fibrillation rats

作　　者：葛敏[1] 单锋[1,2] 唐碧[3] 侯秀杰[4] 

机构地区：[1]蚌埠医学院药学系,安徽蚌埠233030 [2]合肥市第四人民医院药剂科,安徽合肥230022 [3]蚌埠医学院第一附属医院心血管科,安徽蚌埠233004 [4]阜阳市第一人民医院心血管科,安徽阜阳236000

出　　处：《中国应用生理学杂志》2016年第2期128-131,136,共5页Chinese Journal of Applied Physiology

基　　金：国家自然科学基金资助项目(81170046);教育部留学回国人员科研启动基金(第46批);安徽省自然科学基金资助项目(10040606Q44)

摘　　要：目的:探讨二十二碳六烯酸(DHA)对大鼠心房颤动(AF)模型心房肌生理特性的影响及相关机制研究。方法:80只乙酰胆碱-氯化钙混合液敏感的SD大鼠分为对照组(CTL组)、DHA处理组(DHA组)、房颤组(AF组)和房颤+DHA处理组(DHA+AF组),观察房颤持续时间;采用全细胞膜片钳技术记录大鼠心房肌细胞动作电位时程(APD)和双孔钾通道TASK-1电流,Western blot测定大鼠心房组织TASK-1蛋白表达。结果:大鼠尾静脉注射乙酰胆碱-氯化钙混合液后,房颤持续时间随实验天数增加而逐渐延长,DHA干预缩短房颤持续时间。与CTL组相比,AF组大鼠心房肌细胞复极50%时的动作电位时程(APD50)和复极90%时的动作电位时程(APD90)明显缩短,心房肌细胞TASK-1电流密度升高,蛋白表达升高(P<0.05)。与AF组相比,DHA+AF组大鼠心房肌细胞APD50和APD90明显延长,TASK-1电流密度和蛋白表达降低(P<0.05)。结论:DHA具有延长房颤大鼠心房肌细胞APD的作用,可能与其下调心房肌TASK-1蛋白的表达从而降低心房肌细胞TASK-1电流密度有关。Objective： To investigate the effect of docosahexaenoic acid （DHA） on atrial physiological parameter and its related mechanisms in atrial fibrillation rats. Methods： Eighty Sprague-Dawley （SD） rats which were sensitive to acetylcholine-calcium chloride mixture were randomly divided into four groups： control （CTL）, control treated with DHA （DHA）, atrial fibrillation （AF） and atrial fibrillation treated with DHA （DHA ＋ AF）. The duration of atrial fibrillation was measured. The atrial myocyte action potential duration （APD） and TWIK-related acid-sensitive K＋ channels-1 （TASK-1） currents were recorded by whole-cell patch-clamp technique. The expression of TASK-1 at protein level in atrial tissue was detected by Western blot method. Results： Atrial fibrillation of the rats was induced by acetylcholine-calcium chloride mixture, and the duration time of atrial fibrillation was increased with the drug-induced time prolonged. Compared with control group, the time of atrial myocyte action potential duration at 50% repolarization （APD50） and at 90% repolarization （APD90） were significantly shorten in AF group, TASK- 1 current density and TASK- 1 protein expression were increased （ P 〈 0.05）. Compared with AF group, the duration of atrial fibrillation was decreased, the time of atrial myocyte APD50 and APD90 were prolonged, TASK- 1 current density and protein expression were significantly reduced in DHA ＋ AF group （ P 〈 0.05）. Conclusion： DHA can prolong the atrial myocyte APD in atrial fibrillation rats, which may be related to down-regulation of TASK-1 protein expression and decreasing TASK-1 current density in atrial tissue.

关 键 词：心房颤动 二十二碳六烯酸 心房电重构 TASK-1 大鼠 

分 类 号：R541.75[医药卫生—心血管疾病]