Histochemical staining. Its use for detection of glyceraldehyde-3-phosphate dehydrogenase in skeletal muscle.

Histochemical staining of glyceraldehyde-3-phosphate dehydrogenase activity in fresh-frozen muscle tissue may be performed using a beta-nicotinamide adenine dinucleotide (beta-NAD) reduced-dehydrogenase tetrazolium-reductase linked reaction. The phosphate-buffered incubating medium contains glyceraldehyde-3-phosphate, beta-NAD, nitro blue tetrazolium, and edetic acid. This technique produces a fine reticular pattern of blue staining in muscle fibers. In human muscle specimens, type I fibers stain darker than type II fibers.