"All-or-none" cytochrome c oxidase positivity in mitochondria in chronic progressive external ophthalmoplegia: an ultrastructural--cytochemical study.

Abstract

Teased single muscle fibers from 6 patients with chronic progressive external ophthalmoplegia (CPEO) showed a segmental defect in cytochrome c oxidase (COX) activity. On ultrastructural--cytochemical examination, the majority of mitochondria in COX-positive segments were COX-positive, whereas all mitochondria in COX-negative segments were COX-negative. This "all-or-none" COX positivity in mitochondria in CPEO with deleted mitochondrial DNA can be explained by the "threshold effect," which induces the tissue-specific involvement and clinical heterogeneity.

• Authors: T Matsuoka, Y Goto, I Nonaka
• Journal: Muscle & nerve (Muscle Nerve) Vol. 16 Issue 2 Pg. 206-9 (Feb 1993) ISSN: 0148-639X [Print] United States
• PMID: 8381519 (Publication Type: Journal Article)

Chemical References

• Electron Transport Complex IV

Topics

• Electron Transport Complex IV (analysis)
• Humans
• Mitochondria, Muscle (enzymology, ultrastructure)
• Ophthalmoplegia, Chronic Progressive External (metabolism, pathology)