钙调神经磷酸酶基因沉默对肥大乳鼠心室肌细胞瞬时外向钾电流离子通道重构的作用  

Effects of calcineurin gene silencing on the remodeling of transient outward potassium current ionic channel in hypertrophic ventricular myocytes from neonatal rats

作　　者：何炯红[1] 杨龙[1] 夏桂玲 邓娜[1] 杨永曜[1] 田野[1] 扶泽南 黄勇淇 He Jionghong;Yang Long;Xia Gulling;Deng Na;Yang Yongyao;Tian Ye;Fu Zenan;Huang Yongqi.Guizhou(Provincial People＇s Hospital,Guiyang 550002,China)

机构地区：[1]贵州省人民医院心内科,贵阳550002

出　　处：《中华医学杂志》2018年第41期3345-3349,共5页National Medical Journal of China

基　　金：国家自然科学基金资助项目（81260040）;国家临床重点专科建设项目（国卫办医函[2013]544号）;贵州省科学技术厅临床研究中心项目（黔科合平台人才[（2017）5405]）

摘　　要：目的探讨钙调神经磷酸酶（CaN）基因沉默对乳鼠肥大心室肌细胞瞬时外向钾电流（Ito）离子通道重构和动作电位时程（APD）的影响。方法1d龄Sprague-Dawley乳鼠心室肌细胞，培养48h后换无血清培养基，分组干预48h：null组为空腺病毒载体干预，null＋PE组为空腺病毒载体联合苯肾上腺素（PE）干预，Ad-CnAl3shRNAl（A1）组给予重组腺病毒shRNA干扰载体介导沉默编码CaN之A亚基B亚型（CnAl3）基因干预，A1＋PE组为Ad-CnAl3shRNAI联合PE干预。适时荧光定量逆转录PCR检测Kv4．2基因表达。免疫印迹法检测CnAβ和Kv4．2蛋白表达。全细胞膜片钳技术记录Ito及动作电位。结果PE刺激使心室肌细胞肥大，CnAl3蛋白表达上调，Kv4．2基因和蛋白表达下调，Ito离子通道电流密度减小、APD延长。沉默CnAl3基因明显抑制PE刺激的上述效应。结论CnAl3基因沉默抑制PE诱导的肥大乳鼠心室肌细胞It0离子通道重构和APD改变。Objective To investigate the effects of calcineurin gene silencing on the remodeling of transient outward potassium current （Ito） ionic channel and action potential duration （APD） in phenylephrine （PE）-induced hypertrophic ventricular myocytes from neonatal rats. Methods The ventricular myocytes of 1-clay-old Sprague-Dawley rats were isolated and cultured for 48 h. RNA interference mediated by adenovirus carrying short hairpin RNA was used to knock down the gene which encodes the beta subtype of calcineurin A subunit （CnA[3） and the cells were divided into 4 groups as Ad-null group, Ad-null ＋PE group, Ad-CnAβshRNA1 （A1） group and A1 ＋ PE group, and then cultured for 48 h. The gene expression of Kv4. 2 was assayed by real-time reverse transcriptase-polymerase chain reaction. The protein expressions of CnAβ and Kv4. 2 were assayed by Western blot test. Whole cell patch clamp technique was used to record Ito and action potential. Results Treatment of the neonatal rat ventricular myocytes with PE induced the cell hypertrophy, up-regulated the protein expression of CnAβ, attenuated the gene and protein expressions of Kv4. 2 and the Ito current density, and prolonged APD. Silencing of CnAβ in the neonatal rat ventricular myocytes using Ad-CnAβshRNA1 inhibited the aforementioned ability of PE significantly. Conclusion CnAβ gene silencing inhibits the remodeling of transient outward potassium current ionic channel and chan^e of APD in PE-induced hvyertrophic ventricular mvocvtes from neonatal rats.

关 键 词：肥大 钾电流 离子通道 重构 钙调神经磷酸酶 

分 类 号：R541[医药卫生—心血管疾病]