Cellular pathways promoting pulmonary vascular remodeling by hypoxia

Exposure to hypoxia increases pulmonary vascular resistance, leading to elevated pulmonary arterial pressure and, potentially, right heart failure. Vascular remodeling is an important contributor to the increased pulmonary vascular resistance. Hyperproliferation of smooth muscle, endothelial cells, and fibro-blasts, and deposition of extracellular matrix lead to increased wall thickness, extension of muscle into normally non-muscular arterioles, and vascular stiff-ening. This review highlights intrinsic and extrinsic modulators contributing to the remodeling process.