Cytological Studies of Fiber Types in Skeletal Muscle

Abstract

A comparative investigation of the mammalian diaphragm has revealed a correlation between certain cytological aspects of red and white muscle fibers and functional activity. This skeletal muscle presents the advantage of a similar and constant function among the mammals, but its functional activity varies in a quantitative manner. Both the rate of breathing (and hence the rate of contraction of the diaphragm) and metabolic activity are known to be inversely related to body size; and this study has demonstrated a relationship between cytological characteristics of the diaphragm and body size of the animal. Small fibers rich in mltochondria (red fibers) are characteristic of small mammals, which have high metabolic activity and fast breathing rates; and large fibers with relatively low mitochondrial content predominate in large mammals, which have lower metabolic activity and slower breathing rates. In mammals with body size intermediate between these two groups (including the laboratory rat), the diaphragm consists of varying mixtures of fiber types. In general, the mitochondrial content of diaphragm fibers is inversely related to body size. It appears, then, that the red fiber reflects a high degree of metabolic activity or a relatively high rate of contraction within the range exhibited by this muscle.

Transmembrane electrochemical H+‐potential as a convertible energy source for the living cell

“…Indeed, structures of this type have been described in diaphragm [47,48] and skeletal-muscle [49]. Mitochondrial material in the red-flbres of these tissues was found to be organized as structures of three types:…”

Saxitoxin binding to sodium channels of rat skeletal muscles.

“…muscle. The diaphragm, which contains 60 % slow, 20 % fast and 20 % intermediate fibres (Gauthier & Padykula, 1966), has an intermediate site density of 421 #M-2, which is twice the value esti-100 mated in an earlier study (Ritchie & Rogart, 1977b). These estimates were made by assuming that all the binding sites are on the sarcolemma, whereas a considerable proportion of them are presumably in the t-tubules (Bastian & Nakajima, 1974).…”

Tonic Fiber in Mauremys(Clemmys) japonica Jaw Muscle

“…Serial cross sections (about 101.1m) were cut in a cryostat at-20'C, and air dried. Each section was incubated for Ca-activated adenosine triphosphatase at pH 9.4 (Padykula and Herman, 1955), after preincubation at various pH levels (pH 9.4, 5.0, 4.7, 4.5 or 4.3), for succinic dehydrogenase (SDH) activity (Novikoff et al, 1961), and for Ca-adenosine triphosphatase (mitochondrial Ca-ATPase) activity (Fujimoto and Ogawa, 1982), Sudan black B stain (Gauthier and Padykula, 1966) and glycerophosphate dehydrogenase (a-GPDH) (Pearse, 1972), and periodic acid-Schiff reaction (PAS) were used to demonstrate the types of jaw muscle fibers. According to system of Putnam et al, (1980), fibers were classified into four types, as fast twitch glycolytic (FG), fast twitch oxidative glycolytic (FOG), slow twitch oxidative (SO) fibers, and tonic fibers.…”

“…Previous histochemical analyses in the jaw muscles of a turtle have utilized reactions and staining techniques for myosin-ATPase, SDH, mitochondrial Ca-ATPase, Sudan black B, oc-GPDH and PAS to characterize muscle fiber types for contraction speed (Padykula and Herman, 1955), oxidative capacities (Novikoff et al, 1961), glycolytic activity (Wattenberg and Leong, 1960) and respiratory capacities (Gauthier and Padykula, 1966). Histochemical profiles of fiber types in jaw muscles of mammals (Suzuki, 1977; Clark and Luschei, 1981; Rowlerson et al, 1983;Taylor et al, 1973;Lindman et al, 1986), alligators (Sato et al, 1992), and a lizards (Throckmorton and Saubert, 1982) have provided information about contraction speed and metabolic properties in these animals.…”