糖尿病大鼠心室电重构的特征  

The sduty of electrophysiological features of ventricular electrical remodeling on susceptibility of ventricular arrhythmias in diabetic rats

作　　者：杨淑红[1,2] 杨峥[2] 李文星[2] 吴成云[2] 王雪芬[3] YANG Shu-hong;YANG Zheng;LI Wen-xing;WU Cheng-yun;WANG Xue-fen(Department of Breast&.Thyroid Surgery,Renmin Hospital of Wuhan University,Wuhan 430060,Hubei,China;Cardiovascular Research Institute,Renmin Hospital of Wuhan University,Wuhan 430060,Hubei,China;Nursing Department,Renmin Hospital of Wuhan University,Wuhan 430060,Hubei,China)

机构地区：[1]武汉大学人民医院乳腺甲状腺外科,湖北武汉430060 [2]武汉大学人民医院心血管病研究所,湖北武汉430060 [3]武汉大学人民医院护理部,湖北武汉430060

出　　处：《中国心脏起搏与心电生理杂志》2023年第1期43-48,共6页Chinese Journal of Cardiac Pacing and Electrophysiology

基　　金：湖北省自然科学基金资助项目(项目编号:2011CDB504);湖北省卫生计生科研基金资助项目(项目编号:JX6B67)。

摘　　要：目的探讨糖尿病大鼠心室电重构特征。方法将24只健康雄性SD大鼠随机分为对照组和糖尿病组,每组12只,糖尿病组大鼠喂高糖高脂高热量饲料1周,在第2周经腹腔注射链脲佐菌素(65 mg/Kg)诱导。对照组大鼠喂以常规饲料,同期内经腹腔注射同等体积的柠檬酸缓冲液。观察2组的临床体征和空腹血糖(FBG)以及胰岛素敏感指数(ISI)等血液生化指标改变以确定糖尿病模型制备成功,后继续按分组后的饲料喂养8周进行实验。通过记录二组在体心室肌组织单相动作电位,测量动作电位静息膜电位(RMP)、动作电位幅度(APA)、动作电位最大上升速率(Max_(dv/dt))、动作电位平台期电位(plateau P)、动作电位复极化恢复到20%、90%时间(APD_(20)、APD_(90))以及动作电位时程三角测量值(Triangulation)的变化。利用程控刺激和Burst-pacing,测量刺激周长(BCL)为150和_(200) ms时的有效不应期(ERP_(150)和ERP_(200))及其与自律心率下APD_(90)比值(ERP_(150)/APD_(90)和ERP_(200)/APD_(90))改变,监测诱发室性心律失常所需的刺激周长和诱发率。酶解法分离单个心室肌细胞,全细胞膜片钳技术记录测量两组心室肌细胞L-型钙电流(ICa-L)及其电流-电压(I-V)曲线。结果与对照组比较,糖尿病组大鼠出现明显多食、多饮、多尿和体重减轻等临床症状,血液生化指标FBG水平显著增加和ISI值明显降低(P均<0.01),提示糖尿病组模型制备成功。之后,糖尿病组APA和Plateau V明显降低,Max_(dv/dt)减慢,APD_(20)缩短以及APD_(90)和Triangulation显著延长(P均<0.01);同时,糖尿病组的ERP_(150)和ERP_(200)显著延长,ERP_(150)/APD_(90)和ERP_(200)/APD_(90)明显缩短(P均<0.05);糖尿病组诱发室性心律失常的周期均明显延长,诱发率显著增加[(123.57±6.76)ms vs(28.14±3.79)ms,5.5%vs 9%,P均<0.01];在电压钳制方式下,糖尿病组ICa-L的电流密度及幅度显著减小,当钳制电压为+10 mV时,糖尿病组心室肌细胞ICaObjective To investigate of electrophysiological features of remodeling on susceptibility of ventricular arrhythmias in diabetic rats.Methods The 24 healthy and male SD rats were randomly divided into control goup(n=12)and diabetic group(n=12).The rats coming from diabetic models group were fed high-fat and high-glucose diets with varying amounts of hard and suga,after that to be induced by intraperitoneal injection streptozotocin(65mg/Kg)at 8 weeks.And the rats in control group were fed with common diets at same time,after that to be injetcted with an equal volume citrate buffer.After the some changes with clinic signs and fasting blood glucose(FBG)as well as the insulin sensitive index(ISI)were respectively observed and calciulated to justified successfully on diabetic models.Moreover the diabetic rats were kep on feeding 8 weeks until following for experiments.The monophasic action potential(MAP)was recorded with contact electrodes at left ventricular epicardium in rats of 2 groups.And the main cardioelectrophysiological parameters were tested such as rest membrane potential(RMP),action potential amplitude(APA),maximum upstroke velocity (Max_(dv/dt)),action potential plateau potential(Plateau P),action potential duration of 20% and 90%(APD_(20)and APD_(90))as well as triangulation values of repolarization duration (Triangulation=APD_(90)-APD_(40))in rats of two groups.Otherwise,we observed the effective refractory period (ERP)and the rate of ERP and APD_(90)with 150 ms and 200 ms basic cycle length(BCL)(ERP_(150),ERP_(200),ERP_(150)/APD_(90)and ERP_(200)/APD_(90))through using programmed electrical stimulation,and recorded duration and accidence of ventricular arrhythmias by Burst-pacing in rats of control and diabetic group.L-type calcium current (ICa-L)was analyzed via whole-cell patch clamp technique in enzymatically dissociated single rats ventricular myocytes,and current-voltage(I-V)curve was fit via current density as Y axis and command potential as X axis in rats of 2 groups.Results Compared with contro

关 键 词：电生理学 糖尿病 电重构 易感性 L-型钙通道 室性心律失常 

分 类 号：R541.71[医药卫生—心血管疾病] R587.1[医药卫生—内科学] R331.38[医药卫生—临床医学]