Aim To investigate the function of primary culture of rat distal pulmonary arterial smooth muscle cells(PASMC) for in vitro studies of the pathophysiology and medicine intervention of pulmonary circulation diseases,including hypoxic pulmonary hypertension.Methods Microsurgery operations and collagenase digestion were performed to isolate and culture rat distal PASMC.The rat distal PASMC were identified by morphological activity and immunofluorescence of smooth muscle α-actin.Furthermore,the response of intr...