8Aza reversed hypoxic-induced PH progression. (A) Schematic illustration showing the drug treatment protocol. 8Aza was injected intraperitoneally every four days for 28 days for hypoxia or 35 days for SuHx (hypoxia combined with Su5416) PH models. (B, C) Hemodynamic analysis showing the therapeutic effects of 8Aza on Right ventricular systolic pressure (RVSP), and right ventricle (RV)/left ventricle (LV)+S weight ratio, n = 6. (D) Ultrasound analysis showing that 8Aza significantly attenuated the decreased pulmonary artery acceleration time (PAT) and pulmonary artery time integral (PAVTI) caused by either hypoxia alone or SuHx, n = 6. (E) Hematoxylin-eosin staining (HE) staining showing that 8Aza significantly attenuated the increased median wall thickness of pulmonary vascular vessels caused by either hypoxia alone or SuHx, n = 6. NOR, normoxia; HYP, hypoxia, ns, no significance; Statistical analysis was performed with two-way ANOVA followed by Dunnett's test; All values are presented as mean ± SEM. ∗P < 0.05, ∗∗P < 0.01, ∗∗∗P < 0.001.