Comparative study of two classifications of muscle fibres: Consequences for the photometric determination of glycogen according to fibre type in red and white muscle of the pig.

摘要: The present experiment was designed to compare two classifications of myofibres in samples muscles longissimus lumborum (LL) and semispinalis capitis (SC) taken at slaughter from 56 Large White pigs. Comparisons were made for the percentage histological characteristics different types photometric determination glycogen using periodic acid schiff (PAS) staining. Computerized image analysis used (i) classify fibres on basis myosin ATPase activity [Brooke Kaiser (1970) Arch. Neurol. 23, 3669; I, IIA HB], or by combination succino-dehydrogenase (SDH) activities [Ashmore Doerr (1971) Exp. 31, 408: βR, αR, αW] (ii) compute PAS staining luminance individual fibres. Glycogen related metabolites determined muscle homogenates enzymatic techniques. LL showed significantly higher lactate contents than SC a lower average (indicative content). composed predominantly fast-twitch (89%) white (77.3%) contained mainly red (61.1%) (59.3%) In both muscles, comparison indicates that all type I high SDH therefore typed as βR Ashmore Doerr's classification. However, LL, approximately 7% IIB marked thus αR Furthermore, significant differences found between these cross sectional area SC, no pairwise comparisons corresponding classifications. According determination, glycolytic content (fast- slow-twitch) fibres, whereas slow-twitch had levels (red fibres). Corresponding similar levels.