Fig. 2. Increased macrophage LTA₄H over time in developing PH.

(A to D) Representative immunofluorescence images from lung sections stained with antibody to LTA₄H (green) and CD68 (red) from (A) DMSO, (B) 1 week after SU, (C) 2 weeks after SU, and (D) 3 weeks after SU. DAPI (blue) identifies nuclei. Green arrows point to the center of occluded arterioles. Merged panel shows all three stains. (E)Quantitation of LTA₄H staining over time in PH in pulmonary macrophages. LTA₄H⁺, CD68⁺ macrophages were counted per high-power field. (F) LTA₄H mRNA, as measured by RT-PCR. (G) p5-LO⁺ or LTA₄H⁺ macrophages were counted and grouped as <50 µm, 50 to 100 µm, or 100 to 150 µm from the center of the small pulmonary arterioles. n = 6 per group. Scale bar, 50 µm. Kruskal-Wallis test followed by Dunn’s multiple comparisons test for post hoc analyses was used. Data are means ± SEM.