Fig. 4

The α7nAChR signal correlates with changes in wound healing, specifically collagen deposition, and is expressed in rat cardiac fibroblasts. A White dashed box on NS14490 autoradiography images indicate example areas which were sampled for proteomics. B Proteomic heatmap of differentially expressed proteins within the infarct at day 2 (lanes 1–3) versus day 28 (lanes 4–6) which are associated with wound healing, C extracellular structure organization and D the innate immune response. Proteomics was performed in triplicate using pooled tissue from 4 to 6 rats. E Histological evaluation of the macrophage marker CD68 (red) which peaks at day 2 and F total collagen staining by Picro Sirius Red which peaks later. G The α7nAChR autoradiography signal does not correlate with CD68 but instead strongly correlates with H total collagen signal. The correlations graphs consist of global left ventricle, infarct or anterolateral equivalent, infarct border and remote or inferoseptal equivalent regions in 3–6 rats. NS = not significant and **** = P ≤ 0.0001 using Pearson correlation. I Western blot investigation of α7nAChR protein expression in rat cardiac fibroblasts during quiescent conditions (Q), normoxic proliferating conditions (0Hr) and exposure to 1% hypoxia (1–16 h) in proliferating conditions, N = 3