起搏成纤维细胞调控心房肌细胞电生理的机制研究  

Study on the electrophysiological mechanism of atrial myocytes regulated by fibroblasts with pacing

作　　者：付韫韬 陈慧宇 曹真 刘弟世闻 王学文 柯元甲 程燕妮 郭珂欣 赵庆彦[1] Fu Yuntao;Chen Huiyu;Cao Zhen;Liu Dishiwen;Wang Xuewen;Ke Yuanjia;Cheng Yanni;Guo Kexin;Zhao Qingyan(Department of Cardiology,Renmin Hospital of Wuhan University,Cardiovascular Research Institute of Wuhan University,Hubei Key Laboratory of Cardiology,Wuhan 430060,China)

机构地区：[1]武汉大学人民医院心血管内科、武汉大学心血管病研究所、心血管病湖北省重点实验室,武汉430060

出　　处：《中华心律失常学杂志》2023年第3期265-269,共5页Chinese Journal of Cardiac Arrhythmias

基　　金：国家自然科学基金(81970277, 82170312)。

摘　　要：目的探究快速起搏状态下大鼠心房成纤维细胞对心房肌细胞动作电位的影响及其作用机制。方法本研究为前瞻性对照研究,分离大鼠的乳鼠(雌雄不限,体重8~10 g)心房成纤维细胞和心房肌细胞分别进行培养,采用随机数字表法将心房成纤维细胞分为A组(不做任何处理)、B组(在1.0 V/cm的电压、10 Hz频率条件下起搏48 h)、C组[起搏+10 μmol/L中性鞘磷脂酶2抑制剂(GW4869)培养48 h],48 h后收集成纤维细胞上清液,超速离心提取外泌体以2×10^(9)颗粒/ml的量与心房肌细胞共培养。将心房肌细胞分为D组(心房肌细胞+A组外泌体共培养组)、E组(心房肌细胞+B组外泌体共培养组)、F组(心房肌细胞+C组外泌体共培养组)。比较不同状态成纤维细胞来源的外泌体对心房肌动作电位时限的影响。透视电镜分析外泌体形态,纳米颗粒跟踪分析外泌体粒径分布、浓度等指标,膜片钳检测不同组间心房肌细胞动作电位时限[复极达50%和90%时的动作电位时限(APD50和APD90)]。结果与A组相比,B组外泌体分泌量明显增加{[(1.193±0.090)×10^(12)]颗粒/ml对[(1.613±0.100)×10^(12)]颗粒/ml,P=0.006};与B组相比,C组外泌体分泌量相对减少{[(1.613±0.100)×10^(12)]颗粒/ml对[(1.267±0.070)×10^(12)]颗粒/ml,P=0.008};与D组相比,E组心房肌细胞APD50和APD90明显缩短(P=0.021);与E组相比,F组心房肌细胞APD50和APD90则相对延长(P=0.033)。结论快速起搏心房成纤维细胞可促进其外泌体的分泌,而起搏成纤维细胞来源的外泌体则可以缩短心房肌细胞APD50和APD90,增加心房颤动易感性。Objective To investigate the effect of atrial fibroblasts on the action potential of atrial myocytes in rats under rapid pacing and its mechanism.Methods The atrial fibroblasts and atrial myocytes were isolated from rats and cultured separately.The atrial fibroblasts were randomly divided into group A(control group),group B(paced for 48 hours at 1.0 V/cm and 10 Hz),and group C(paced for 48 hours at 1.0 V/cm and 10 Hz with 10μmol/L of neutral sphingomyelinase 2 inhibitor GW4869).After 48 hours,the supernatant of fibroblasts was collected and extracellular vesicles were isolated by ultracentrifugation.Atrial myocytes were co-cultured with exosomes at a concentration of 2×10^(9) particles/ml.The atrial myocytes were divided into group D(co-cultured with extracellular vesicles from group A),group E(co-cultured with extracellular vesicles from group B),and group F(co-cultured with extracellular vesicles from group C).The effects of extracellular vesicles from different fibroblast groups on atrial myocyte action potential duration(APD)were compared.Transmission electron microscopy was used to analyze the morphology of extracellular vesicles,and nanoparticle tracking analysis was used to measure the particle size distribution and concentration of extracellular vesicles.Patch clamp technique was used to measure the action potential duration(APD)at 50%and 90%repolarization(APD50 and APD90),respectively,in atrial myocytes from different groups.Results Compared with group A,the secretion of extracellular vesicles was significantly increased in group B{[(1.193±0.090)×10^(12)]particles/ml vs.(1.613±0.100)×10^(12)]particles/ml,P=0.006},while it was relatively decreased in group C{[(1.613±0.100)×10^(12)]particles/ml vs.[(1.267±0.070)×10^(12)]particles/ml,P=0.008}.Compared with group D,the APD50 and APD90 of atrial myocytes were significantly shortened in group E(P=0.021).Compared with group E,the APD50 and APD90 of atrial myocytes were relatively prolonged in group F(P=0.033).Conclusion Rapid pacing promotes the secre

关 键 词：心房颤动 外泌体 成纤维细胞 心房肌细胞 动作电位 

分 类 号：R541.75[医药卫生—心血管疾病]