Reduced Expression of Endothelial Nitric Oxide Synthase in the Lungs of Patients with Pulmonary Hypertension

Pulmonary hypertension is generally characterized by increased thickening of the walls of pulmonary arteries, narrowing of the pulmonary-artery lumen, increased pulmonary vascular resistance, and right-sided heart failure. 1 – 3 Clinically, patients have increasing dyspnea, cyanosis, precordial discomfort, anginal pain, and cardiomegaly. 1 – 3 Histologically, pulmonary arteries with such resistance, particularly those less than 100 μm in diameter, show various degrees of intimal thickening and muscular hypertrophy. 1 , 4 , 5 Pulmonary hypertension can be either idiopathic (primary) or due to other disease conditions. A number of humoral factors have been implicated in the pathogenesis of pulmonary hypertension, but there is no evidence that any . . .