Stereologic analysis of dystrophic chicken muscle.
Stereologic methods have been used to estimate the volume and surface densities of sarcoplasmic reticulum (SR) and T tubules of normal and dystrophic chicken pectoralis muscle fibers. The surface and volume densities of the T system in dystrophic muscle fibers showed large increases compared with normal muscle fibers; the surface and volume densities of the SR showed large decreases. In addition, the SR and T system in dystrophic fibers undergo changes in shape. The tubules of the free SR become much narrower; the T system becomes dilated and vesiculated. Dystrophic fibers, on the average, are much larger than normal but maintain the same sarcolemmal surface/fiber volume ratio as normal fibers. Alterations in the surface and volume densities of the dystrophic sarcotubular system may account for some of the altered contractile properties of these muscles.
D000818:Animals; D002645:Chickens; D008433:Mathematics; D008931:Mitochondria, Muscle / Q000473:pathology; D009132:Muscles / Q000473:pathology*; D009137:Muscular Dystrophy, Animal / Q000473:pathology*; D009210:Myofibrils / Q000473:pathology; D012508:Sarcolemma / Q000473:pathology*; D012519:Sarcoplasmic Reticulum / Q000473:pathology*