Figure 1.
Connexin 43 location S-nitrosylation and NOX2 expression in dystrophic hearts at 2 and 10 months of age. (A) Panel of representative confocal images of cardiac sections of control and mdx mice for Cx43 and counterstained for nuclei (propidium iodide, PI). The arrows indicate lateralized Cx43. (B) Western blot analysis for the NADPH oxidase-2 subunits p22 and NOX2. The upper panels show representative Western blots for p22, NOX2 and GADPH as loading control. The graphs depict the quantification of p22 and NOX2, normalized to GADPH levels. (C) S-nitrosylation of Cx43 in cardiac homogenates assessed by the biotin-switch method. The left panel shows representative Western blots for S-nitrosylated and total Cx43 in 2- and 10-month-old BL10 and mdx hearts. The graphs at the right depict the quantification of nitrosylated and total Cx43. (D) Assessment of cardiac contractility evaluated as dP/dtmax in isolated hearts from controls (BL10) and mdx mice, two and ten months of age, using increasing concentrations of isoproterenol as adrenergic agonist. (E) Evaluation of the occurrence of arrhythmic episodes in the same hearts submitted to isoproterenol perfusion. The n is indicated in the bars or the legend of each graph. * p < 0.05; ** p < 0.005; *** p < 0.001 for comparisons indicated by the brackets, ANOVA with Newman–Keuls post-hoc test.