A COMBINED MYOSIN ATPASE AND ACETYLCHOLINESTERASE HISTOCHEMICAL METHOD FOR THE DEMONSTRATION OF FIBER TYPES AND THEIR INNERVATION PATTERN IN SKELETAL-MUSCLE

An improved, combined staining method for myofibrillar ATPase (m-ATPas e) and for acetylcholinesterase activity is described. This method all ows the observations, on the same slide, of the classical histochemica l m-ATPase profile following the Brooke and Kaiser technique and the n euromuscular junction morphology. Thus the pattern of innervation, ner ve ending structure and number of nerve endings along the fibres is sh own simultaneously for the basic differentiation between slow and fast fibres. The use of acidic and alkaline preincubation allows better vi sualization of endplate morphology and avoids the masking effect of a positive m-ATPase reaction. The technique has been validated on skelet al muscles from avian and mammalian species.