Evans blue dye uptake analyses of quadriceps muscles and serum CK measurements. (A) Evans blue dye (EBD) fluorescence photomicrographs of quadriceps muscle sections from dysferlin-null, mdx and DKO mice at six months of age. Scale bar: 100 μm. (B) Serum creatine kinase (CK) levels were significantly different (P < 0.001) between DKO mice (n = 6) and the other groups (n = 5, 4 and 6 for WT, dysferlin-null and mdx mice, respectively). Values for mdx mice were significantly different from those for WT mice (P = 0.018). For clarity, significance is shown only for the comparisons with the DKO mice. ***P < 0.001.