Disruption of cellular signaling identified in pulmonary arterial hypertension

Impairment of a key signaling cascade in the pulmonary blood vessels plays an important role in pulmonary arterial hypertension, a Yale study has found. The study appears in the advance online publication of Nature Medicine. Pulmonary arterial hypertension (PAH) is a disease caused by an increase of blood pressure in the blood vessels of the lungs. If untreated, the majority of patients with the disease will succumb to heart failure and death. PAH is characterized by the formation of lesions in the lungs composed of abnormally proliferating cells of the endothelium (cell tissue that lines blood vessels and the heart) and vascular smooth-muscle cells. Recent studies have described the role of the gene apelin in the signaling process that maintains normal pulmonary vascular function. Apelin levels have been found to be significantly reduced in patients with PAH.