ACTA1 and idiopathic pulmonary arterial hypertension: Moreover, we (3) found elevated AK4 levels in α-SMA-positive cells in remodeled pulmonary vessels from IPAH patients, and reduced proliferation and glycolytic metabolism of IPAH-PASMCs after AK4 knockdown, supporting a potential in vivo role of AK4 in the process of pulmonary vascular remodeling.