Reduced expression of endothelial nitric oxide synthase in the lungs of patients with pulmonary hypertension.

Abstract

Pulmonary hypertension is characterized by abnormal thickening of the pulmonary arteries and increased pulmonary vascular resistance. Nitric oxide is a potent endothelium-derived vasorelaxant substance and an inhibitor of smooth-muscle-cell growth. Nitric oxide is produced in various cell types by the action of an enzyme, nitric oxide synthase. We compared the expression of endothelial nitric oxide synthase in the lungs of control subjects with that in the lungs of patients with pulmonary hypertension.