Figure 3: Membrane stability in muscle fibers before and after injury. Evans Blue Dye (EBD) was used to evaluate sarcolemmal integrity within the TA muscles of mice after injury. EBD is detected under fluorescence microscopy (568 nm, insets show high magnification) and the presence of the protein-bound dye inside the muscle fiber indicates damage to the sarcolemma. (a) cryosection of an uninjured wild-type TA muscle from animals injected with EBD. (b) cryosection of an injured wild-type TA; the injury protocol used here was not enough to cause significant membrane damage in wild-type muscle. (c) cryosection of an uninjured mdx TA from animals injected with EBD. (d) cryosection of an injured wild-type TA; intracellular EBD indicates damage to the sarcolemma, which occurred frequently in the mdx injured muscles. (e) Histogram showing quantification of EBD-positive fibers. Without injury, the number of EBD-positive (EBD+) fibers was not significantly different between wild type and mdx. Only the mdx animals showed a significant increase in the number of positively labeled fibers after injury. Scale bar = 200 μm. : significant difference from noninjured, .