ISSN:
0003-276X
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Medicine
Notes:
Muscle fibers of the sternomastoid and the tongue of the rat were characterized histochemically according to mitochondrial distribution (succinic dehydrogenase), as well as reactivity for the alkali- and acid-stabile “myofibrillar” adenosine triphosphatases. The principal fiber types of the sternomastoid were the large, “white” AαβM fibers and the smaller, “intermediate” BβD and “red” CαL fibers (figs. 1, 2, 3). The unusual musculature of the tongue was populated by diminutive AαM and CαM fibers, and variants thereof; all with relatively high mitochondrial content (figs. 4, 5, 6).Reinnervation of the sternomastoid muscle by the hypoglossal nerve caused most fibers of the sternomastoid to assume histochemical profiles reminiscent of those commonly observed in the tongue. However, the BβD fibers of the sternomastoid persisted in near usual numbers and disposition (fig. 17), despite their reinnervation by a nerve normally destined for a muscle lacking that particular fiber type. Thus, there are as yet unrecognized factors, possibly of neural origin, though more likely of muscle origin (genetic), that impose restrictions on the metabolism-regulating functions of substitute motoneurons.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/ar.1091820407
