益母草注射液对糖尿病心肌病大鼠心肌细胞凋亡和增殖活性的作用研究

目的探讨中药益母草注射液(LHS)对链脲佐霉素(STZ)制备的糖尿病心肌病(DCM)大鼠心肌细胞凋亡和增殖活性的作用。方法2004年3月至2004年9月于汕头大学医学院第二附属医院内分泌科建立STZ诱导DCM的大鼠模型,将实验大鼠随机分为未治疗组、LHS治疗组和正常对照组,16周龄时处死,观察心肌细胞的凋亡百分数(TUNEL法)、Fas、FasL、Bax、Bcl-2、增殖细胞核抗原(PCNA)的表达(免疫组化法)、心肌细胞超微结构的改变(电镜)。结果与DCM组相比,DCM给药组大鼠心肌肌节对位仅见少部分错位,肌原纤维无溶解,线粒体结构完整;心肌细胞中促凋亡因子Fas、FasL和Bax的表达降低,抑制凋亡的Bcl-2/Bax比值增加,心肌细胞凋亡百分数降低,差异均有显著性(P<0·05);PCNA阳性细胞数增多,差异有显著性(P<0·05)。结论LHS治疗后,心肌细胞凋亡比未治疗组明显减少,而增殖活性明显增强,LHS能有效防治大鼠DCM,改善超微结构的异常。

Effects of Leonurus heterophyllus sweet injection on myocardial cell apoptosis and proliferation activity in the diabetic cardiomyopathy rats

Objective To explore the effects of Leonurus heterophyllus sweet injection(LHS)on myocardial cell apoptosis and proliferation activity in the diabetic cardiomyopathy rats induced by STZ.Methods From March to September of 2004,STZ-induced DCM model was established.The diabetic rats were divided into three groups:untreated DCM group,treated group by LHS injection and normal control group.At the end of 16 weeks,myocardial tissue of the rats was collected as experimental material to examine apoptosis by using TUNEL,electromicroscopic changes(ultrastructure)and related gene expression(Fas,FasL,Bax,Bcl-2)as well as proliferating cell nuclear antigen(PCNA)with immunohistochemistry method.Results 1.Compared with the DCM group,only a few myotomes of cardiac myocytes in LHS-treated group were out of their positions.There was no myofibril melt and the mitochondria structure kept intact.2.Compared with the DCM group,the numbers of myocardial cell apoptosis were significantly decreased(P<0.05).The expression of pro-apoptosis factors Fas,FasL and Bax were significantly decreased(P<0.05),but Bcl-2/Bax was significantly increased(P<0.05).3.PCNA positive cells were significantly increased(P<0.05).Conclusion LHS injection therapy can markedly reduce myocardial cell apoptosis and increase proliferation activity.LHS can prevent diabetic rats from developing DCM and ameliorate the ultrastructure.