【摘要】 目的观察过量运动对肌营养不良症模型鼠(mdx鼠)骨骼肌的损害作用,以及成肌细胞移植对运动诱导损害肌纤维的保护作用。方法采用分离消化法对C57新生鼠的成肌细胞进行体外培养、纯化鉴定后,肌肉注射到mdx鼠左后肢,右后肢肌注DMEM作对照。成肌细胞移植后1个月,让mdx鼠作运动试验3d后,静脉注射Evans蓝,次日取骨骼肌作冰冻切片,行dystrophin免疫荧光检测。荧光显微镜下,观察Evans蓝和dystrophin阳性纤维数,图像分析比较。结果未移植肢体有2682%±1485%的肌纤维显示Evans蓝染色,而移植侧骨骼肌只有1037%±287%的肌纤维显示Evans蓝染色。两者相比有显著差异(P<005)。移植侧肢体有4832%±654%的肌纤维dystrophin阳性,对照侧几乎没有dystrophin阳性肌纤维。Evans蓝染部分没有dystrophin表达。结论成肌细胞移植对运动诱导损害的肌纤维具有防护作用。更多还原

【Abstract】 AIM: To observe skeletal muscle damage of mdx mice after overload exercise, and protection to muscle damage induced by exercise due to myoblast transplantation (MTT). METHODS: Muscle samples of C 57 mice were minced and digested with trypsin, and myoblasts were cultured ex vivo , purified and detected by immunohistochemistry stains. The myoblasts were injected into muscle of left limb of mdx mice, whereas the right limb was injected with DMEM liquid as control. Mice were submitted to exercise for 3 days starting 1 month after MTT, and then Evans blue was injected intravenously through the tail vein. The muscle cryostat sections of mdx mice were made, and then detected the immunofluorescence of dystrophin. Under a fluorescence microscope, the number of fiber stained with Evans blue and dystrophin was counted, analyzed quantitatively with image software. RESULTS: Under a fluorescence microscope, only 10 37%±2 87% muscle fibers in the myoblast grafted muscles were stained with Evans blue. In contrast, 26 82%±14 85% muscle fibers in right control muscles were stained. Significant differences between these two groups were showed ( P<0 05 ). A average of 48 32%±6 54% of muscle fibers were dystrophin positive in grafted muscles, whereas few dystrophin positive muscle fibers in control side. None of the fibers expression dystrophin was stained with Evans blue. CONCLUSION: MTT in mdx mice has a protective effect against muscle damage by exercise. [更多还原