Quantitative axon terminal and end-plate morphology in amyotrophic lateral sclerosis

An axon-end-plate double stain yielded more synaptic detail than the older methylene blue stain of the muscle biopsy specimen. Application of the double stain to amyotrophic lateral sclerosis confirmed earlier and well-known findings of denervation, abnormal end-plates, and axonal sprouting. Little new data emerged, however, and the sprouting index seemed to mislead. As in several previous investigations, muscle from normal human subjects showed evidence for at least past if not current denervation, substantiating the need for continued rigorous controls in such studies.