Histologic evaluation of mdx, mdx:Myog-deleted, and wild-type hindlimb muscle.

(A) Hematoxylin and eosin-stained mdx and mdx:Myog-deleted muscle sections both displayed classic characteristics of regeneration, which include wide variations in myofiber diameter and centrally located nuclei, that were not observed in wild-type samples. (B) Van Gieson staining for collagen and elastin revealed similar levels of fibrosis in mdx and mdx:Myog-deleted muscle sections that were not observed in wild-type samples. (C) Ultrastructural analysis with TEM showed that mdx:Myog-deleted muscle sections have reduced mitochondrial swelling when compared to mdx samples. Arrows point out mitochondria. Arrow heads point out sarcomeric Z-lines; note the abnormal Z-lines in mdx muscle.