Ne. Chayen et al., FISH MUSCLE STRUCTURE - FIBER TYPES IN FLATFISH AND MULLET FIN MUSCLES USING HISTOCHEMISTRY AND ANTIMYOSIN ANTIBODY LABELING, Journal of muscle research and cell motility, 14(5), 1993, pp. 533-542
In studies of the myosin crossbridge interaction with actin in vertebr
ate muscles, the muscles of bony fish have the unique advantage for ul
trastructural work that the A-band has a simple 'crystalline' lattice
of myosin filaments. However, the anatomy and physiology of these fish
muscles is relatively poorly understood compared with the rabbit, chi
cken or frog muscles conventionally used for crossbridge studies. Here
the fibre types in fish fin muscles have been characterized to allow
sensible selection of single fish fibres for ultrastructural studies.
The fibre type compositions of the fin muscles of mullet, plaice, sole
and turbot were examined by histochemistry and immunohistochemistry u
sing polyclonal antibodies raised against various myosin isoforms: fis
h slow, fish fast, mammalian fast (type IIA) and chicken tonic myosins
. In the mullet, fin muscles were composed of variable proportions of
fast and slow fibres. In the three flatfish, the fin muscle showed a z
onal arrangement with slow fibres, binding anti-slow myosin antibody,
next to the skin (alpha region). The bulk of the muscle, distal to the
skin, was a typical fast muscle both histochemically and in its react
ion with antibodies (delta region). Between these two regions there ma
y be one (sole) or two (turbot, plaice) intermediate zones (beta and g
amma regions) comparable to the pink/intermediate layer of myotomal mu
scle. In the plaice fin muscle, two kinds of slow fibre could be disti
nguished immunohistochemically.