FIG. 4.

Oxidative stress pretreatment increases vascular remodeling following ischemia-reperfusion injury. Images show heart sections from PBS-treated (A, C) or PQ-treated (B, D) mice 1 month following IR injury stained for desmin (red, A, B) or CD31 (red, C, D) and imaged with Abcg2 lineage label (green). Desmin-positive cardiomyocytes are negative for ZsGreen (A, B), whereas CD31-positive endothelial cells are positive for ZsGreen (C, D) in both PBS- and PQ-treated mice. Nuclei are labeled with DAPI (blue) for all images. Capillary density (scored by total CD31-positive area normalized to nuclei per field) in the peri-scar region is increased following IR injury in PQ-pretreated mice (127.6 ± 13.8) compared to control (PBS-treated; 80.5 ± 8.3) mice, *P < 0.05 (E). The number of CD31-positive cells coexpressing ZsGreen (Abcg2-labeled) was scored by the number of merged pixels normalized to nuclei per field and is increased in the peri-scar region in PQ-treated mice (40.1 ± 5) versus PBS-treated mice (27.5 ± 3.8), *P < 0.05 (F). n = 6 mice per group for quantitative analysis. Scale bar = 50 μm. IR, ischemia reperfusion; PQ, Paraquat dichloride; PBS, phosphate-buffered saline.