C1q肿瘤坏死因子相关蛋白9对大鼠心肌梗死后室性心律失常的影响

The effect of C1q/tumor necrosis factor-related protein-9 on ventricular arrhythmia after myocardial infarction in rats

目的研究C1q/肿瘤坏死因子相关蛋白-9(CTRP9)对心肌梗死(MI)大鼠电重构的作用,探讨CTRP9对MI后室性心律失常(VA)的影响。方法体重为180~200g的健康SD大鼠64只,随机分为四组:假手术对照(Control)组,心肌梗死(MI)组,Ad-CTRP9+MI(Ad-CTRP9)组,Ad-GFP+MI(Ad-GFP)组。Ad-CTRP9组与Ad-GFP组分别通过颈静脉给药Ad-CTRP9和Ad-GFP,5天后予以MI造模。MI14天后,每组随机选取6只大鼠,利用蛋白质免疫印迹法测定心肌组织中CTRP9、KChIP2和Kir2.1的表达量;每组随机选取10只大鼠,利用体表心电图记录心率(HR)、RR间期、QRS波时限、QT间期和QTc间期,并同时分析心率变异性(HRV);利用自制电极测定梗死周边区有效不应期(ERP),记录梗死周边区的心外膜的单向动作电位(MAP),并分别计算动作电位复极完成20%、50%和90%的时间(APD20、APD50和APD90);通过S1S1刺激测量心室MAP交替阈值(ALT);四组给予Brust刺激,比较VA的诱发率。结果与Control组比较,MI组QTc间期延长[(55.75±3.95)ms vs(42.00±1.93)ms,P<0.05],HRV窦性RR间期的标准差(SDNN)降低,低频LF(nu)、LF/高频(HF)增加,HF降低(P均<0.05)。与Ad-GFP组比较,Ad-CTRP9组QTc间期缩短[(47.69±2.73)ms vs(54.06±3.31)ms,P<0.05],SDNN、HF增加,LF与LF/HF降低,P均<0.05)。与Control组比较,MI组ERP、APD20、APD50、APD90增加[(71.67±2.13)ms vs(44.00±3.02)ms,(25.81±1.14)ms vs(21.73±1.28)ms,(42.43±2.66)ms vs(31.01±1.62)ms,(113.78±5.71)ms vs(71.10±3.27)ms,P均<0.05]。与Ad-GFP组比较,Ad-CTRP9组ERP、APD20、APD50、APD90降低[(59.83±2.61)ms vs(75.33±1.97)ms,(22.54±1.16)ms vs(26.25±1.37)ms,(34.46±0.96)ms vs(42.53±2.28)ms,(79.75±3.51)ms vs(115.43±4.06)ms,P均<0.05]。与Control组比较,MI组ALT增加[(119.5±1.06)ms vs(70.00±0.93))ms,P<0.05]。与Ad-GFP组比较,Ad-CTRP9组ALT降低[(89.75±1.16)ms vs(112.5±0.73)ms,P<0.05)]。与Control组比较,MI组VA发生率增加(10/10 vs 0/10,P<0.05)。与Ad-GFP组比较,Ad-CTRP9组VA发生率降低(3/10 vs 10/10,P<0.05)。与Control组比较,MI组CTRP9、KChIP2和Kir2.1蛋白表达降低(P均<0.05)。与Ad-GFP组比较,Ad-CTRP9组CTRP9、KChIP2和Kir2.1蛋白表达增加(P均<0.05)。结论CTRP9可以显著改善MI后心室电生理性质,具有潜在的抗VA作用。

Objective To clarify the effect of C1q/tumor necrosis factor-related protein-9 on the electrical and structural reconstruction of myocardial infarction rats,so as to explore the effect of CTRP9 on arrhythmias of myocardial infarction.Methods Sixyt-four healthy SD rats weighing 180-200 g were randomly divided into four groups:sham operation control(Control)group,myocardial infarction(MI)group,AD-CTRP9+MI(Ad-CTRP9)group,and Ad-GFP+MI(AdGFP)group.Ad-CTRP9 group and Ad-GFP group were administered with Ad-CTRP 9 and Ad-GFP sepsrately through the jugular vein,and then conducted left anterior descending(LAD)ligation 5 days later,before which anesthetized with 3%pentobarbital sodium 30 mg/kg by intraperineal injection.The LAD branch of the three groups was ligated to make MI animal models.The Control group were all through thoracotomy but not ligating the coronary artery.Two weeks after myocardial infarction,10 rats were randomly selected from each group,the expression of CTRP9,KChIP2 and Kir2.1 in myocardial tissue was measured by western blotting;10 rats were randomly selected from each group,program-controlled stimulation was used to determine the effective refractory period in the peripheral area of ventricular infarction;body surface cardiogram was used to record heart rate(HR),RR interval,QRS complex duration,QT interval and QTc interval simultaneous analysis of heart rate variability(HRV).The self-made electrode was used to measure ERP in the peripheral area of the infarction,and the monophasic action potential(MAP)of the epicardium at the above-mentioned sites was recorded.Then 20%,50%and 90%of duration for action potential repolarization(APD20,APD50 and APD90)was calculated respectively.The S1 S1 dynamic pacing method was used to determine the APD alternation threshold and induction rate of ventricular arrhythmia in four groups.Results Compared with the Control group,the QTc interval[(55.75±3.95)ms vs(42.00±1.93)ms,P<0.05]in MI group was significantly propagated,the SDNN of HRV time domain analysis in MI group was significantly decreased.Compared with the Control group,spectrum analysis shows that the values of LF(nu)and LF/HF were significantly increased,while HF(nu)was significantly decreased,all P<0.05);ERP[(71.67±2.13)ms vs(44.00±3.02)ms,P<0.05],APD20[(25.81±1.14)ms vs(21.73±1.28)ms,P<0.05],APD50[(42.43±2.66)ms vs(31.01±1.62)ms,P<0.05]and APD90[(113.78±5.71)ms vs(71.10±3.27)ms,P<0.05)],APD alternation threshold[(119.5±1.06)ms vs(70.00±0.93))ms,P<0.05)],the incidence of ventricular arrhythmia events(10/10 vs 0/10,P<0.05)were significantly increased in MI group.Compared with Ad-GFP group,CTRP9 significantly shortened QTc interval[(47.69±2.73)ms vs(54.06±3.31)ms,P<0.05],increased SDNN,HF(nu),decreased LF(nu)and LF/HF,all P<0.05)].In addition,compared with Ad-GFP group,CTRP9 decreased ERP[(59.83±2.61)ms vs(75.33±1.97)ms,P<0.05],APD20[(22.54±1.16)ms vs(26.25±1.37)ms,P<0.05],APD50[(34.46±0.96)ms vs(42.53±2.28)ms,P<0.05]and APD90[(79.75±3.51)ms vs(115.43±4.06)ms,P<0.05)]in the periphery of ventricular infarction.CTRP9 also decreased the APD alternation threshold[(89.75±1.16)ms vs(112.50±0.73)ms,P<0.05)and the incidence of ventricular arrhythmia events(3/10 vs 10/10,P<0.05).Besides,compared with the Control group,the expression levels of CTRP9,KChIP2 and Kir2.1 proteins in the MI group was decreased.Compared with the Ad-GFP group,the expression levels of CTRP9,KChIP2 and Kir2.1 proteins in the Ad-CTRP9 group was significantly increased.Conclusion CTRP9 can significantly improve ventricular electrophysiological properties after MI,and has a potential anti-VA effect.[Chinese Journal of Cardiac Pacing and Electrophysiology,2020,34(6):583-588]