Matsuoka T, Goto Y, Yoneda M, Nonaka I
Division of Ultrastructural Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan.
J Neurol Sci. 1991 Dec;106(2):193-8. doi: 10.1016/0022-510x(91)90257-8.
Histopathologic findings were examined in skeletal muscle biopsies from 6 patients with myoclonus epilepsy with ragged-red fibers (MERRF) who had an A to G base substitution at mitochondrial DNA (mtDNA) nucleotide pair 8344. In addition to variation in fiber size and ragged-red fibers, all specimens in cross sections showed focal cytochrome c oxidase (CCO) deficiency, suggesting that this finding is crucial in elucidating the role of the mutant mtDNA in the pathogenesis of this disorder. Along the length of single muscle fibers, defects in CCO activity were distributed segmentally with blurred borders in 5 patients which were in contrast with segmental defects with sharply delineated borders seen in chronic progressive external ophthalmoplegia with deleted mtDNA. These morphologically heterogeneous defects in CCO activity may in part be due to differing populations of and distributions of wild and mutants mtDNAs.
对6例患有肌阵挛性癫痫伴破碎红纤维（MERRF）且线粒体DNA（mtDNA）核苷酸对8344处存在A到G碱基替换的患者的骨骼肌活检组织进行了组织病理学检查。除了纤维大小变化和破碎红纤维外，所有横断面标本均显示局灶性细胞色素c氧化酶（CCO）缺乏，这表明该发现对于阐明突变mtDNA在该疾病发病机制中的作用至关重要。在单根肌纤维的长度上，5例患者的CCO活性缺陷呈节段性分布，边界模糊，这与线粒体DNA缺失的慢性进行性眼外肌麻痹中所见的边界清晰的节段性缺陷形成对比。CCO活性的这些形态学异质性缺陷可能部分归因于野生型和突变型mtDNA的不同群体和分布。
