FIG. 7.
AAV-mediated ΔR4/ΔC microdystrophin expression did not compromise contractile properties of the normal EDL muscle. The left EDL muscles of 4.5-month-old mdx mice were infected with AV.ΔR4/ΔC. The contralateral right EDL muscles served as sham-infected controls. Muscle contractile assays were performed when mice were 9 months of age. (A) Force–frequency relationship between sham-infected (open bar) and AV.ΔR4/ΔC-infected (filled bar) EDL muscles. No statistically significant difference was seen between the two groups ( P > 0.05). (B) Relative tetanic force drop during 10 cycles of eccentric contraction. Open circles, sham-infected EDL muscles (mean − SEM); closed circles, EDL muscles infected with AV.ΔR4/ΔC (mean + SEM). N = 3 pairs. There was no statistical difference between AV.ΔR4/ΔC-infected and sham-infected groups ( P > 0.05).