Immunohistochemical microquantification of fast-myosin in frozen histological sections of mammalian skeletal muscles.

Fast-myosin in frozen histological sections was quantified by an immunohistochemical micromethod based on the ELISA. Frozen tissue sections mounted on glass slides were used analogously to the antigen-precoated wells of ELISA plates. The intensity of immunoreactivity of frozen sections to an anti-fast-myosin monoclonal antibody was quantified directly from the color developed with the second antibody coupled with peroxidase using phenol-4-aminoantipyrine as a substrate. Fast-myosin levels in the masseter muscles of pigs, rats, and rabbits were 185 +/- 6, 223 +/- 9, and 178 +/- 12 mg/g of total protein, respectively, and those in the gastrocnemius muscles from cows, pigs, goats, rats, and rabbits were 172 +/- 12, 211 +/- 7, 177 +/- 9, 211 +/- 10, and 205 +/- 10 mg/g, respectively. In the masseter of cows and goats, fast-myosin was not detected. The results obtained by this immunohistochemical micromethod were in good agreement with those obtained by histomorphometrical and biochemical analyses. This immunohistochemical micromethod could be used to quantitatively evaluate the muscle contractile characteristics that determine meat quality.