三七总皂苷对小鼠柯萨奇B3病毒性心肌炎诱导型一氧化氮合酶的影响

目的：探讨三七总皂苷对小鼠柯萨奇B3病毒所致病毒性心肌炎模型中诱导型一氧化氮合酶（iNOS）表达的影响，为病毒性心肌炎的治疗寻找新的理论依据。方法：选用近交系4～6周龄雄性BALB／C小鼠84只，随机分为3组：空白对照组（C组）24只，心肌炎组（V组）30只，治疗组（T组）30只。于病毒接种后第8天、第15天、第21天分别采血后处死小鼠并留取心脏标本，采用免疫组化法检测心肌iNOS蛋白表达，硝酸还原酶法测定血清NO含量，光镜及透射电镜观察心肌组织病理及细胞超微结构改变。结果：（1）V组和T组小鼠心肌细胞iNOS免疫组化染色表达呈阳性，c组iNOS免疫组化染色阴性；（2）T组与V组比较，心肌细胞iNOS表达在第15天及第21天明显降低，差异有统计学意义（P〈0．05、P〈0．01）；（3）T组在第15天及第21天血清NO含量较V组明显降低（P〈0．05）；（4）光镜下T组炎症细胞浸润较V组轻，炎症积分在第15天及第21天明显低于V组（P〈0．05、P〈0．01）；（5）电镜下V组及T组可见肌原纤维溶解断裂，线粒体膜消失，含溶酶体丰富的单核巨噬细胞浸润，c组小鼠心肌未见上述变化。结论：三七总皂苷可降低小鼠病毒性心肌炎iNOS的表达，从而减少NO释放，可能对病毒性心肌炎有一定治疗作用。

The Effect of Panax Notoginseng Saponin on Inducible Nitric Oxide Synthase in Mouse with Viral Myocarditis induced by Coxsachie Virus B3

Objective： To observe the effect of panax notoginseng saponin on inducible nitric oxide synthase in mouse with viral myocarditis induced by coxsachie virus B3. Methods： The inbred male BALB/C mice of 4 -6 weeks were randomly divided into three groups as follows： a blank group （group C）, a viral myocarditis group （group V） , and a therapy group （group T）. The mice in each group were killed and heart specimens were preserved on the 8th, 15th, and 21st day respectively after infections. The hearts tissue slides were stained by immunohistochemistry （IHC） for iNOS and the content of NO was measured by nitrale reduetase. The histological and ultrastructure changes were observed under light microscope and electron microscope. Results： （ 1 ） The result of iNOS IHC staining： myocardial cells had positive expression in the group V and group T, but the group C was negative. （2） The expression of iNOS in the group T was significantly lower than that in the group V on the 15th and 21st day （ P〈0.05 and 0.01, respectively）. （3） Compared with the group V, serum NO level in the group T showed significantly lower on the 15th day and 21st day （P〈0.05）. （4） Compared with the group V, there was slight inflammatory in the group T, and the histopathologic scores were decreased obviously on the 15th day and 21 st day （P〈0.05 and 0.01, respectively）. （5） The myocardial observation through electron microscopy： in the V and group T myofibril was dissolved and mitochondrial membrane disappeared. Mononuclear cell infiltration also can be seen under electron microscopy, which contained many lysosomes. In the group C myocardial ceils were normal. Conclusions： The panax notoginseng saponin can reduce the expression of iNOS and the content of NO. It may have some therapeutic effect to viral myocarditis.