VEGFA and pulmonary arterial hypertension: However, the frequently studied Sugen-hypoxia animal model that closely mimics PAH with the development of vascular remodeling and plexiform lesions uses a VEGF receptor (VEGFR2) antagonist in conjunction with hypoxia, which is known to upregulate VEGF levels, demonstrating that VEGF signaling is important for the development of PH.