CAV1 and pulmonary arterial hypertension: Studies with CAV1 knockout mice also found that these mice suffered from pulmonary hypertension with medial thickening, muscularization of distal pulmonary vessels and loss of total pulmonary artery surface area, as well as thickened alveolar septa, hypercellularity and an increase in extracellular fibrillar deposits [41, 42].