Figure 8.

Medial wall thickness was quantified on αSMA-stained lung sections (A) and elastin stained sections (B), the percent of muscularized blood vessels was quantified in vWF and αSMA double-stained lung sections (C) and the RV/LV free wall thickness ratio was measured in HE-stained heart tissue sections as a marker for right ventricular hypertrophy (D) in rat pups kept in RA (open bars) or 100% O₂ for 10 days (shaded bars). RA and O₂ pups were injected twice a day for 10 days with 0.9% NaCl or 2.5 μg kg⁻¹ BMP9. Values are expressed as mean ± SEM. N = 8 for medial wall thickness and vascular muscularization and N = 10 for RV/LV ratio. Differences between groups were analyzed by one-way ANOVA, followed by Tukey's multiple comparisons test. ^*p < 0.05 and ^***p < 0.001 vs. RA controls. Three independent experiments were performed. LV, left ventricle; RV, right ventricle.