连夏宁心方对室性心律失常模型大鼠心肌组织CaM、CaMKⅡ、RyR2蛋白表达的影响

Effect of Lianxia Ningxin Formula(连夏宁心方) on the Expression of CaM,CaMKⅡ and RyR2 in Myocardial Tissue of Ventricular Arrhythmia Model Rats

目的探讨连夏宁心方防治室性心律失常(VA)的可能作用机制。方法48只SD大鼠随机分为空白组、模型组、稳心颗粒组及连夏宁心方低、中、高剂量组,每组8只。稳心颗粒组给予稳心颗粒1.75g/(kg·d)灌胃,连夏宁心方低、中、高剂量组分别给予连夏宁心方0.68、1.35、2.71g/(kg·d)灌胃,空白组和模型组给予1.0ml/100g生理盐水灌胃。灌胃21天后,除空白组外其余各组大鼠通过舌下静脉注射肾上腺素制备VA大鼠模型。记录肢体标准Ⅱ导联心电图,观察造模后15 min内室性早搏(VP)、室性心动过速(VT)出现时间及VT持续时间。Western blot法检测心肌组织钙调蛋白(CaM)、钙/钙调蛋白依赖性蛋白激酶Ⅱ(CaMKⅡ)及兰尼碱受体2(RyR2)蛋白含量。结果与空白组比较,模型组大鼠心肌组织CaM、CaMKⅡ蛋白表达显著升高,RyR2蛋白表达显著降低(P<0.05或P<0.01)。与模型组比较,稳心颗粒组VT出现时间延长,VT持续时间缩短,心肌组织CaM、CaMKⅡ蛋白表达明显下降,RyR2蛋白表达显著升高(P<0.05或P<0.01);连夏宁心方高剂量组大鼠VP出现时间延长,心肌组织CaM蛋白表达明显下降(P<0.05);连夏宁心方低、中剂量组大鼠VP、VT出现时间延长,VT持续时间缩短,心肌组织CaM、CaMKⅡ蛋白表达明显下降,RyR2蛋白表达显著升高(P<0.05或P<0.01)。与连夏宁心方高剂量组比较,连夏宁心方中、低剂量组及稳心颗粒组大鼠心肌组织CaM蛋白表达明显降低,RyR2蛋白表达显著升高(P<0.05或P<0.01)。结论连夏宁心方可能通过下调心肌组织CaM、CaMKⅡ蛋白表达,上调RyR2蛋白表达防治VA,且低、中剂量效果较优。

Objective To explore the effects and possible mechanism of Lianxia Ningxin Formula(连夏宁心方)in treatment of ventricular arrhythmia(VA).Methods Forty-eight healthy male SD rats were randomly divided into blank group,model group,Wenxin Granule(稳心颗粒)group,and Lianxia Ningxin Formula low,medium and high dose groups,with eight rats in each group.Wenxin Granule at 1.75 g/(kg·d)was given by gavage to the Wenxin Granule group,while Lianxia Ningxin Formula at 0.68,1.35 and 2.71 g/(kg·d)were administered by gavage in the corresponding low,medium and high dose groups;normal saline at 1.0 ml/100 g was given by gavage to both the blank group and the model group.After 21 days of administration,rats in all groups but the blank group were injected with adrenaline through the sublingual vein to develop VA model.The standard Ⅱ lead electrocardiogram of the limbs was recorded;the occurring time of ventricular premature beats(VP)and ventricular tachycardia(VT),and the lasting time of VT within 15 minutes after modeling were assessed.Western blotting was used to detect the protein content of cardiac tissue calmodulin(CaM),calcium/calmodulin-dependent protein kinase Ⅱ(CaMKⅡ)and ryanodine receptor 2(RyR2)in myocardial tissue.Results Compared to the blank group,the model group had significantly increased CaM and CaMKⅡ protein expression and decreased RyR2 protein expression in the myocardial tissue(P<0.05 or P<0.01).Compared to the model group,Wenxin Granule group postponed the occurring time of VT and shortened the lasting time of VT,reduced the CaM and CaMKⅡprotein expression,and increased RyR2 protein expression in the myocardial tissue(P<0.05 or P<0.01).Lianxia Ningxin Formula high dose group had prolonged the occurring time of VP and down-regulated the CaM protein expression(P<0.05);Lianxia Ningxin Formula low and medium dose groups significantly delayed the occurring time of VP and VT,shortened the lasting time of VT,decreased CaM and CaMKⅡ protein expression,and increased RyR2 protein expression(P<0.05 or P<0.01).Compared to those in the Lianxia Ningxin Formula high dose group,the expression of CaM protein in myocardial tissue was significantly decreased,and the expression of RyR2 protein was significantly increased in the low,medium dose groups and Wenxin Granule group(P<0.05 or P<0.01).Conclusion Lianxia Ningxin Formula may achieve antiarrhythmic effects by down-regulating the expression of CaM and CaMKⅡ and up-regulating the expression of RyR2 in the myocardial tissue,and the low and medium doses have better effects.