Omura et al. [144] found that EC AMPK activity is reduced in distal pulmonary arteries of PAH patients and an experimental mouse model with chronic normobaric hypoxia (10% O2)-induced PAH at 4 weeks; specifically, PDGF-BB and fibroblast growth factor-2 (FGF-2) expression in PASMCs was increased, promoting HPH development. This evidence concerns the gene FGF2 and pulmonary arterial hypertension.