A successive histochemical staining for succinate dehydrogenase and "reversed"-ATPase in a single section for the skeletal muscle fibre typing.

A procedure is described which simplifies the classification of skeletal muscle fibres in that it allows a simultaneous evaluation of both the oxidative capacity and the intensity of "reversed" ATPase of the fibres, and thus enables to distinguish three fibre types - SO, FOG and FG - in one tissue section. After preincubation at pH 4.1-4.2 the cryostat section is incubated for succinate dehydrogenase (SDH) and subsequently for "reversed"-ATPase. This is followed by the fixation with neutral buffered formaldehyde. The results of typing of chicken, minipig and rabbit fibres in a single muscle section stained with this technique are identical to those obtained with the usual method based on a comparison of serial sections of which one is stained for SDH activity the other for "reversed"-ATPase activity.