四逆汤对异丙肾上腺素诱导的大鼠心肌纤维化Smad2和Smad7的影响

目的 观察四逆汤对异丙肾上腺素诱导的大鼠心肌纤维化Smad2和Smad7的影响。方法 Wistar大鼠随机分为对照组、模型组和四逆汤组。模型组及四逆汤组给予注射异丙肾上腺素，对照组注射生理盐水。四逆汤组给予四逆汤灌胃，对照组和模型组均给予生理盐水灌胃。4周后,各组行Masson染色和电镜分析；通过免疫组化方法检测心肌Smad 2和Smad 7蛋白在心肌的表达；RT-PCR法检测Smad 2和Smad 7 mRNA表达。结果 Masson染色示模型组心肌胶原纤维IOD值为9303，而四逆汤组为2459，对照组为4224，提示模型组心肌纤维化较四逆汤和对照组明显；模型组心肌Smad 2蛋白IOD值为20275，mRNAI OD值为0.919；而四逆汤组Smad 2蛋白IOD值为9949，mRNAI OD值为0.561，提示模型组Smad 2表达明显高于四逆汤组（P<0.05)；模型组心肌Smad 7蛋白IOD值为25667，mRNAI OD值为0.222，而四逆汤组Smad 2蛋白IOD值为93 147，mRNAI OD值为0.412，提示模型组Smad 7表达明显低于四逆汤组（P<0.05)。结论 四逆汤可以有效抑制异丙肾上腺素所致的大鼠心肌纤维化，其机制可能与下调Smad 2表达和上调Smad 7表达有关。

Effects of Sini Decoction on the Expressions of Smad2 and Smad7 in Isoproterenol Induced Myocardial Fibrosis Rats

Objective To explore the effects of Sini Decoction(SD) on the expressions of Samd2 and Smad7 isoproterenol(Iso) induced myocardial fibrosis rats.Methods Totally 19 Wistar rats were randomly divided into 3 groups,i.e.,the control group,the model group,and the SD group.Iso was injected to rats in the model group and the SD group,while normal saline was injected to rats in the control group.SD was given to rats in the SD group by gastrogavage,while normal saline was administered to rats in the control group and the model group by gastrogavage.Four weeks later Masson staining and electron microscopic analysis were performed in each group.The protein and mRNA expressions of Smad2 and Smad7 were detected using immunohistochemical assay and RT-PCR.Results Masson staining showed the IOD value of the myocardial collagen fiber was 9 303 in the model group,2 459 in the SD group,and 4 224 in the control group,indicating the myocardial fibrosis was more obvious in the model group than in the SD group and the control group.The IOD value of Smad2 protein was 20 275 and the mRNA IOD of Smad2 protein was 0.919 in the model group,while they were respectively 9 949 and 0.561 in the SD group,indicating the protein and mRNA expressions of Smad2 were obviously higher in the model group than in the SD group(P<0.05).The IOD value of Smad7 protein was 25 667 and the mRNA IOD of Smad7 protein was 0.222 in the model group,while they were respectively 93 147 and 0.412 in the SD group,indicating the protein and mRNA expressions of Smad7 was obviously lower in the model group than in the SD group(P<0.05).Conclusion SD could effectively inhibit Iso induced myocardial fibrosis,and its mechanism may be associated with down-regulating the expression of Smad2 and up-regulating the expression of Smad7.