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Updated: Jul 29, 2026

A Rapid Automated Protocol for Muscle Fiber Population Analysis in Rat Muscle Cross Sections Using Myosin Heavy Chain Immunohistochemistry
Published on: March 28, 2017
Transformation of fibre types in muscular dystrophies
In the normal human skeletal muscle, slow and fast forms of troponin I are segregated in type I and type II cells, respectively. Muscle biopsies from different dystrophies showed a large number of intermediate cells that stained with antibodies to both fast and slow troponin I. Intermediate cells of variable size were scattered at random and did not show a motor unit distribution as generally seen in some neuromuscular disorders. The preponderance of a particular cell type depended on the type of dystrophy. Except for dystrophia myotonica, all cases showed presence of small cells that looked like regenerating cells.
In the normal human skeletal muscle, slow and fast forms of troponin I are segregated in type I and type II cells, respectively. Muscle biopsies from different dystrophies showed a large number of intermediate cells that stained with antibodies to both fast and slow troponin I. Intermediate cells of variable size were scattered at random and did not show a motor unit distribution as generally seen in some neuromuscular disorders. The preponderance of a particular cell type depended on the type of dystrophy. Except for dystrophia myotonica, all cases showed presence of small cells that looked like regenerating cells.
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