病毒性心肌炎心肌线粒体结构功能变化及大剂量维生素C干预作用

The effects of high dosage vitamin C on myocardial mitochondrial structure and function in mice with viral myocarditis

目的：探讨病毒性心肌炎（ＶＭＣ）小鼠心肌线粒体结构和功能，并用大剂量维生素Ｃ进行干预。方法：雄性Ｂａｌｂ／ｃ小鼠随机分为柯萨奇Ｂ３病毒（ＣＶＢ３）感染组（ＩＧ）、ＣＶＢ３感染加大剂量维生素Ｃ治疗组（ＩＶＧ）和对照组（ＣＧ）。采用电镜和形态计量学方法观察心肌线粒体形态、数量和膜磷脂定位，用酶细胞化学法分析心肌线粒体细胞色素氧化酶（ＣＣＯ）和琥珀酸脱氢酶（ＳＤＨ）活性。结果：ＩＧ小鼠心肌线粒体大量破坏，ＣＣＯ和ＳＤＨ活性降低，膜磷脂严重缺失、定位改变（Ｐ ＜０．０５～ ０．０１）。不同时相点ＩＶＧ上述各项指标均较ＩＧ显著改善（Ｐ ＜０．０５～０．０１）。结论：ＶＭＣ心肌线粒体结构严重破坏、功能明显下降，大剂量维生素Ｃ能有效保护心肌线粒体结构和功能。

Objective: To explore the changes of myocardial mitochondrial structure and function in mice with viral myocarditis,and to observe the interventional effects of high dosage vitamin C. Methods: The male Balb/c mice were randomly divided into three groups:coxsackie B3 virus(CVB3) infection group(IG), CVB3 infection group with high dosage vitamine C treatment (IVG) and control group(CG). The morphology, membrane phospholipid, as well as activities of cytochrome oxidase(CCO) and succinate dehydrogenase(SDH) of myocardial mitochondria were studied by using transmission electron microscope,morphometry and enzyme cytochemical method respectivly. Results: As compared to CG, a large number of mitochondria of IG was damaged, the activities of CCO and SDH of mitochondria declined,the apparent mitochondrial membrane phospholipid deletion and localization change were observed ( P<0.05 ～0.01). All of these were improved significantly in IVG (P<0.05～0.01). Conclusion: The myocardial mitochondrial structure was damaged apparently and its funtions declined obviously in viral myocarditis.High dosage vitamin C can have effects against myocardial mitochondrial structure damage and function decline.