Simultaneous cytochemical demonstration of muscle fiber types and acetylcholinesterase in muscle fibers of dystrophic chickens

Abstract

A cytochemical procedure is described which allows the simultaneous observation of different types of muscle fibers and their motor end plates. The procedure utilizes an assay for myofibrillar adenosine 5′-triphosphatase (ATPase) activity followed by an assay for acetylcholinesterase (AChE) activity. This combined assay eliminates the necessity for using serial sections for observation of these two parameters. This combined assay increases the apparent AChE activity such that sites of AChE activity are revealed which are not visualized when using the AChE assay alone. In muscles from chicks with hereditary muscular dystrophy, it is shown that initially dystrophic fibers contain nuclei which react strongly for AChE activity. Subsequently many fibers exhibit an intense reaction for AChE activity over a major portion of their cell surface. AChE activity is also found along the splits of fragmenting fibers and on the periphery of necrotic vacuoles.