Duchenne/Becker肌营养不良骨骼肌病变的超微结构特征

Ultrastructural features of skeletal muscle in the patients with Duchenne/Becker muscular dystrophy

目的探讨Duchenne/Becker肌营养不良(D/BMD)患儿肌细胞损伤的特征性超微结构改变。方法2000年6月至2007年7月对东南大学医学院附属南京第二医院收治的6例D/BMD进行临床分析和肌肉组织的组织学检查,进行ATP(pH9.4)、NADH-TR酶组织化学染色、抗肌萎缩蛋白免疫组化染色,对超微结构进行观察分析。结果通过酶组织化学和免疫组织化学检测,此6例均明确诊断为D/BMD。超微结构检查:同一标本中可见肌纤维病变轻重不一,损伤肌纤维均有肌浆膜破坏,细胞外基质、基底膜破坏,肌细胞边缘有成束的细丝。严重病变细胞内肌丝、肌节、线粒体、核均有破坏。结论D/BMD患儿骨骼肌细胞普遍存在肌浆膜和基底膜损伤。

Objective The muscular injuries in patients with Duchenne/Becker muscular dystrophy （D/B MD） may be shown by electron microscopy. The ultrastructural features of skeletal muscular damages were explored. Methods The clinical analysis in six patients with D/B MD manifested as hepatitis was performed. The histochemical stains of ATP （pH9.4） and NADH-T, the immunohistochemical stains of dystrophin and the ultrastructural observation in muscle were operated. Results By histochemical and immunohistochemical stains, the diagnosis of D/B MD was demonstrated in all the patients. Electronic microscopy revealed the presence of various injuries in the same sample of muscle. There were the injuries of sarcolemmas and basement membrane, abnormality of extracellular matrix and fracture of collagen in all six patients. The collagen was separated to filament that clumped on sarcolemmas. The damages of cell organisms, namely accumulation of glycogen, congregation and fragmentation of mitochondria, destruction of myofilament and breakdown of nucleus, appeared in the cells with severe injuries. Conclusion By uhrastructural observation, the muscular injuries in patients with D/B MD present the destruction of sarcolemmas and basement membrane.