Fig. 6

Alterations of calcium homeostasis, TRCP3 mRNA and protein expression levels, and skeletal muscle contraction before and after AAV2/9-MD treatment in DMD^mdx rats. A Typical immunoblot labeled to reveal WT dystrophin (Dyst), MD, TRPC3 and GAPDH in EDL and diaphragm (Dia) muscle homogenates obtained from Vehicle-WT, Vehicle-DMD^mdx and MD-DMD^mdx rats. B Resting cytosolic calcium concentration ([Ca²⁺]_c) and C Resting sarcolemmal permeability to calcium (SPCa). [Ca²⁺]_c and SPCa were measured in Fura2 loaded single fibers from mechanically isolated bundles of EDL muscles in vehicle-treated WT and DMD^mdx rats, and AAV2/9-MD treated DMD^mdx rats (MD-DMD^mdx). Bars represent mean ± SEM values of [Ca²⁺]_c and SPCa in n EDL muscle fibers from N animals (n/N are indicated at the bottom of the bars). *: significantly different from mean value measured in WT muscle fibers; $: significantly different from mean value measured in Vehicle-DMD^mdx muscle fibers; One-way ANOVA and Fisher LSD post-hoc test, P < 0.05. D Maximal diaphragm contraction amplitude measured in vivo by echography. E: Whole muscle maximal tetanic tension measured in vitro in EDL from Vehicle-WT, Vehicle-DMD^mdx and MD-DMD^mdx rats. F and G Expression of TRPC3 mRNAs and proteins, measured by RTq-PCR and western blot, respectively, in EDL muscle extracts from Vehicle-WT, Vehicle-DMD^mdx and MD-DMD^mdx rats. D–G bars represent ± SEM values measured in N animals (N are noted at the bottom of the bars). *: significantly different from mean value measured in WT muscle; $: significantly different from mean value measured in Vehicle-DMD^mdx muscles; Kruskal–Wallis test and Conover-Iman post-hoc test, P < 0.05