Furthermore, ATP released from lung vascular endothelial cells through CALHM1/2 channels can also serve as an important ligand to stimulate PASMC proliferation and migration through activation of purinergic receptors (P2Y and P2X) in PAH and PH (Visovatti et al., 2016; Hennigs et al., 2019; Strassheim et al., 2020). This evidence concerns the gene CALHM1 and pulmonary arterial hypertension.