SMAD2 and pulmonary arterial hypertension: Tang et al. used Ginsenoside Rg1 to treat hypoxia‐induced PAH rats and found that hypoxia could promote the inflammation and vascular remodeling of pulmonary artery tissue in rats, and the levels of TGF‐β1 and p‐Smad2/3 in pulmonary artery tissue were significantly upregulated.