This Article  • References  • Full text PDF  • Reply to article  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Contact me when this article is cited  Related Content  • Similar articles in this journal

Daniel B. Drachman, MD; Douglas M. Fambrough, PhD

Arch Neurol. 1976;33(7):485-488.

Abstract
• An underlying neurogenic abnormality has recently been postulated in the muscular dystrophies. To test this hypothesis, we applied a widely accepted criterion of denervation—ie, an increase in extrajunctional acetylcholine (ACh) receptor sites—to muscle biopsy specimens from nine patients with myotonic dystrophy and three with amyotrophic lateral sclerosis (ALS). The ACh receptor sites were determined by means of iodine 125-labeled -bungarotoxin binding, measured by scintillation counting and autoradiography.

None of the myotonic dystrophy muscles showed increased extrajunctional ACh receptor sites, even in the smallest fibers. By contrast, muscle biopsy specimens from patients with ALS showed notably increased extrajunctional ACh receptor sites, especially in the small fibers.

Our findings do not support the hypothesis of a neurogenic defect in myotonic dystrophy.

Author Affiliations
From the Department of Neurology, Johns Hopkins University School of Medicine (Dr Drachman), and the Department of Embryology, Carnegie Institution of Washington (Dr Fambrough), Baltimore.

Footnotes
Accepted for publication July 15, 1975.

Reprint requests to Johns Hopkins Hospital, 601 N Broadway, Baltimore, MD 21205 (Dr Drachman).