Duchenne型肌营养不良症与正常肌组织体外成肌过程的对比研究

A Comparative Study on the Differences of in vitro Myogenesis between Patients with Duchenne Muscular Dystrophy and Normal Person

应用Ｄｅｓｍｉｎ免疫细胞化学和透射电镜观察体外培养肌管，发现其胞浆Ｄｅｓｍｉｎ染色阳性，肌丝分化形成肌节，表明肌管是体外培养肌细胞的成熟阶段。对９例Ｄｕｃｈｅｎｎｅ型肌营养不良症（ＤＭＤ）患者和５例正常人肌组织体外培养肌细胞成肌过程进行动态观察，发现ＤＭＤ体外培养肌细胞有一定的生长、成熟能力，９例均能形成肌管，但分裂增殖期明显长于正常人组（Ｐ＜０．０５），分裂增殖晚期细胞明显退变，初生肌管不能进一步成熟。以培养５周为界，ＤＭＤ组所形成的肌管较正常组瘦短且核数少（Ｐ＜０．０５）。ＤＭＤ体外培养肌细胞存在肌管形成的延缓和分化成熟的障碍。

Myotube morphology was studied by desmin immunocyto chemistry and electronmicroscopy.The results showed that desmin was dispersive and myofibrillar sarcomeres had been development in the cytoplasm,myotube display was the maturity stage of skeletal muscle cell in vitro.Using the culture containing human fetal muscle extract(HFME),muscular cultures were established from 9 cases of Duchenne muscular dystrophy(DMD)and 5 cases of age-matched normal control biopsies.Both DMD and normals mononucleated cells outgrew from explant between 4～5days in vitro,While prolonging culture,the population of mononucleated cells rapidly increased and became organized into confluenced monolayer cultures after 14d.But the duration range of DMD myotube formation was 28～31d,which was longer than that in normals which was 18～22 d(P<0.05>).In the early stage of normal myotube formation phase,most of the prefused myoblasts were more slender than those with refractile perinuclear granules in DMD which were still in the late proliferation phase.In myotube formation phase,not only the frequency but also the developmental maturity(number of neuclei,length,width)of the DMD myotubes were fewer and poorer than those in the normals(Kruskal-Wallis test,P<0.05).The results mentioned above indicated that the myogenesis defect existed in DMD in vitro.