ESTIMATION OF FIBER TYPE COMPOSITION OF 11 SKELETAL-MUSCLES FROM NEW-ZEALAND WHITE RABBITS BETWEEN WEANING AND EARLY MATURITY

  • 1 January 1977
    • journal article
    • research article
    • Vol. 123  (APR) , 501-513
Abstract
Muscle fiber types [in rabbits] were differentiated on the basis of histochemical staining reactions for Ca2+-ATPase at pH 9.4, cytochrome oxidase, succinate dehydrogenase and L-glycerol-3-phosphate:menadione oxidoreductase activities. Fibers were divided into 3 main categories in white muscles and 2 in red muscles. It was impossible to relate fiber types between the white and red muscles although certain metabolic similarities were noticed. The fiber type distribution was quantitated. Between weaning and early maturity most muscles showed little change in fiber type composition, particularly when the Ca2+-ATPase was used as the criterion. Many muscles showed an uneven distribution of fiber types in transverse sections; this was particularly so in the cases of longissimus, semitendinosus, soleus and semimembranosus propius muscles. The methods successful in resolving fiber types in mature muscles were not as capable of resolving fiber types in neonatal muscles.