丹参酮ⅡA对兔急性心肌梗死后室性心律失常及离子通道蛋白基因表达的影响  

Effects of Tanshinone ⅡA on Ventricular Arrhythmias and Ion Channel Protein Gene Expressions after Acute Myocardial Infarction in Rabbits

作　　者：朱琳[1] 王照华[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院急诊内科,武汉430030

出　　处：《华中科技大学学报（医学版）》2014年第5期501-505,共5页Acta Medicinae Universitatis Scientiae et Technologiae Huazhong

基　　金：国家自然科学基金青年基金资助项目(No.81001571)

摘　　要：目的探讨丹参酮ⅡA对家兔急性心肌梗死后室性心律失常和离子通道蛋白基因表达变化的影响,阐述丹参酮抗心律失常的可能机制。方法 24只家兔随机分为假手术组、心肌梗死组、丹参酮组、卡维地洛组,每组各6只。采用结扎冠状动脉左前降支法制作急性心肌梗死模型,观察家兔偶发室性早搏(OVPBs)、频发室性早搏(FVPBs)、室速(VT)的发生率和心肌梗死面积的变化,并采用实时荧光定量PCR方法观察心肌钙调蛋白(CAM)、钙调蛋白激酶Ⅱ(CAMKⅡ)、L型钙离子通道(LTCC)、钾离子通道Kv4.2mRNA的表达变化。结果与假手术组相比,心肌梗死组OVPBs、FVPBs和VT的发生率明显增高(均P<0.05),梗死面积明显增大(均P<0.05),CAM、CAMKⅡ、LTCC mRNA表达明显增高(均P<0.05),ItoKv4.2mRNA表达明显降低(均P<0.05);与心肌梗死组相比,丹参酮组和卡维地洛组的OVPBs、FVPBs和VT的发生率明显降低(均P<0.05),梗死面积明显减小(均P<0.05),CAM、CAMKⅡ、LTCC mRNA表达明显降低(均P<0.05),ItoKv4.2mRNA表达明显增高(均P<0.05);与卡维地洛组相比,丹参酮组的OVPBs、FVPBs和VT的发生率增高,但差异无统计学意义(均P>0.05),梗死面积增大(均P<0.05),CAM、CAMKⅡ、LTCC mRNA表达增高(均P<0.05),ItoKv4.2mRNA表达降低(均P<0.05)。结论钙调蛋白和离子通道蛋白基因表达的变化可能是急性心肌梗死室性心律失常发生的重要机制,丹参酮ⅡA能显著降低其发生率,缩小心肌梗死面积,其分子机制可能与钙调蛋白和离子通道蛋白基因表达变化有关。Objective To investigate the effects of tanshinoneⅡ A on ventricular arrhythmias and ion channel protein gene expressions after acute myocardial infarction （AMI） in rabbits in an attempt to elucidate the possible action mechanism of tanshinone in the treatment of arrhythmias.Methods A total of 24 rabbits were randomly divided into 4 groups （n=6 each）：sham group,myocardial infarction （MI） group,tanshinone Ⅱ A （Tan） group,carvedilol （Car） group.AMI animal models were established by occluding the rabbit left anterior descending （LAD） coronary artery.The incidence of occasional premature ventricular contractions （PVCs）,frequent PVCs,and ventricular tachycardia （VT） was measured,and the changes of myocardial infarct size was observed.The mRNA expressions of calmodulin （CAM）,calmodulin kinase Ⅱ （CAMK Ⅱ）,L-type calcium channel （LTCC） and potassium ion channel Kv4.2 were detected by reverse transcription polymerase chain reaction （RT-PCR）.Results The incidence of occasional PVCs,frequent PVCs and VT,and the myocardial infarct size was significantly increased in the MI group as compared with the sham group （P〈 0.05）.AMI also resulted in a significantly upregulated expression of CAM,CAMK Ⅱ and LTCC mRNA and a downregulated expression of Kv4.2 mRNA in myocardial tissue （P〈0.05 for all）.Administration of tanshinone Ⅱ A and carvedilol significantly decreased the incidence of occasional PVCs,frequent PVCs and VT,and the myocardial infarct size （P〈0.05）.They reduced the mRNA expressions of CAM,CAMK Ⅱ and LTCC （P〈0.05for all） and elevated the Kv4.2 mRNA expression （P〈0.05）.Although the incidence of ventricular arrhythmias was higher in the Tan group than in the Car group,there was no significant difference （P〉0.05）.The myocardial infarct size and the mRNA expressions of CAM,CAMK Ⅱ and LTCC were increased and the mRNA expression of Kv4.2 was significantly decreased in the Tan group when compared with those in the Car group （P�

关 键 词：丹参酮ⅡA 急性心肌梗死 室性心律失常 钙调蛋白 通道蛋白 

分 类 号：R541.4[医药卫生—心血管疾病]