Incidence of Z band streaming and myofibrillar disruptions in skeletal muscle from healthy young people

Abstract

Skeletal muscle tissue was obtained from the vastus lateralis or peroneus brevis muscles of 34 healthy volunteers. Focal and extensive areas of Z band streaming and disruption of myofibrillar architecture without Z band streaming were quantified in Araldite-embedded specimens examined in the phase microscope. Extensive areas of Z band streaming in more than 2.0 percent of fibers was present in only two of the 34 volunteers. Myofibrillar disruptions without Z band streaming was much less common than Z band streaming. The size of extensive areas of Z band streaming or myofibrillar disruptions was quantified by counting the number of adjacent fibrils and contiguous sarcomeres occupied by either type of lesion. These data should be of use in determining if such lesions are present in excessive amounts in suspected pathologic material.

Ultrastructure and Activity of Some Enzymes of Energy Metabolism of Skeletal Muscle in Experimental Energy Deficiency

“…Similar ultrastructural alterations have been re ported earlier [16,31,34], The disorganisa tion in the internal architecture of fibers in the localized areas is taken to be a nonspe cific indicator of damage, and has been re ported in normal human subjects [26]. In the present study, in addition to the findings described above, there were varied mito chondrial alterations.…”

Subsarcolemmal Vermiform Deposits in Skeletal Muscle, Associated with Familial Cardiomyopathy: Report of Two Cases of a New Entity

“…Z band abnormalities have been described in a num ber of diseases [12] such as central core disease, Schwartz-Jampel syndrome, myotonic dystrophy, poly myositis, dermatomyositis, and inclusion body myositis [3]. There is experimental evidence that Z band stream ing is associated with ischemia [8]; the presence of this streaming and a scalloped surface in the affected fibers of our cases suggests the possibility of an ischemic process.…”

Muscle biopsy and muscle fiber hypercontraction: a brief review

“…Hypercontracted ®bers have been noted in dystrophic muscle, although in general other signs of degeneration and necrosis are also observed (Cullen and Fulthorpe 1975;Schmalbruch 1973Schmalbruch , 1975. As noted above, hypercontracted ®bers are typically not present in muscle samples obtained by open biopsy from healthy individuals (Meltzer et al 1976;Moulds et al 1977;Schmalbruch 1973Schmalbruch , 1975. A high [Ca 2+ ] has been implicated in the hypercontraction and degeneration noted in diseased skeletal muscle (Oberc and Engel 1977;Schmalbruch 1975;Tay et al 1992).…”

“…In the open biopsy technique, large muscle samples (@2±3 cm in length, 0.5 cm 2 in cross-section) can be obtained and are often clamped prior to excision, thus helping to prevent hypercontraction (Bossen 2000;Moulds et al 1977;Schmalbruch 1975). Hypercontracted ®bers have either not been observed (Meltzer et al 1976;Moulds et al 1977;Schmalbruch 1975), or have been observed only rarely in healthy muscle samples obtained by open or surgical biopsy (Schmalbruch 1973). In muscle samples obtained by open biopsy from healthy subjects, Moulds et al (1977) reported hypercontraction only at the cut ends of muscle ®bers.…”