【摘要】 目的　本研究通过观察 Duchenne和 Becker型肌营养不良症 (DMD/BMD)患者超微病理的特征 ,从亚细胞水平上探讨其病因和发病机制。方法　应用电子显微镜 ,采用超薄切片和冷冻蚀刻技术观察 9例 DMD/BMD患者超微结构的改变。结果　 (1) DMD/BMD透射电镜发现 :“Z”线模糊不清 ,宽窄不一 ,间距变窄 ,肌原纤维明带增宽 ,肌原纤维过度收缩。血管内皮细胞肿胀 ,毛细血管闭塞 ,闭塞的毛细血管内皮细胞中可见大量饮液泡 ;肌原纤维粗细不等 ,肌浆网明显扩张 ,肌浆网侵入肌原纤维间 ,呈虫食样 ,肌浆网中可见浓缩的包涵物。肌丝排列紊乱 ,肌浆网管扩张 ,肌丝间网聚集 ;线粒体中间段大空泡 ,肌丝间网较明显 ,糖原颗粒聚积。 (2 ) DMD骨骼肌冷冻蚀刻电镜图像示 :肌原纤维间存在同心圆状排列的板层体 ;粗细肌丝排列紊乱 ,正常的六角形点阵结构消失。结论　(1) DMD/BMD超微结构改变表现为肌纤维的坏死和细胞膜的破坏。 (2 )肌纤维内毛细血管闭塞 ,血管内皮细胞肿胀 ,间质毛细血管血流瘀滞。表明 DMD/BMD可能还存在血液循环障碍 ,有待进一步证实。更多还原

【Abstract】 Objective To observe the substuctural fearures in DMD/BMD using ultrathin section and freeze-etching technique by electron microscope and to explore the etiology and pathogenesis on subcellular level.Methods The ultrastucture of muscles in 9 patients with DMD/BMD was observed under electronic microscopy using ultrathin section and fre eze-etching technique.Results (1) By using transmission electr on microscope,"z"line was unclear,spacing got narrow,myofibril supercontracted, “I” band of myofibril broaden,endothelial cell of blood vessel swellen,capilla ry occluded,a great deal of drinking fluid bubble was detected in the endothelia l cell of occluded capillary,and myofibril differed in size.“Z”line differed i n thickness.Sarcoplasmic reticulum dilated evidently,invaded to myofibril as wor m eatting. Inspissated content in the Sarcoplasmic reticulum was detected. Myofi lament arranged disorderly.The duct of sarcoplasmic reticulum dilated. Reticulum between myofilaments collected ;big vacuoles were detected in the mitochondria. Reticulum between myofilaments was appearent. Glycogen granule collected.(2) Freeze-etching of skeletal muscles with DMD/BMD by electr on microscope showed that :Board layer body as concentric circle present in the myofibril. My ofilament arranged disorderly,and the normal strcture as hexagon losed.Conclusion (1)This study showes that in DMD/BMD ultrastructure changes are muscle fiber necrosis and cell’s membrane destruction;(2) Capillary in the muscle fiber occludes,the endothelial cell of b lood vessel swells,blood steam of the capillary in interstitial obstructes.The change reveal e that there is dysfunction of blood circulation in DMD/BMD ,which needs to be proved.更多还原