Impairment of Endothelium-Dependent Pulmonary-Artery Relaxation in Chronic Obstructive Lung Disease

CHRONIC obstructive lung disease causing hypoxemia leads to the development of pulmonary hypertension and cor pulmonale. 1 The prognosis of cor pulmonale is determined by the severity of the pulmonary hypertension. 2 However, the manner in which prolonged alveolar hypoxia causes chronic pulmonary hypertension remains unknown. 3 In rats, the induction of chronic hypoxia causes ultrastructural changes of the endothelial cells of pulmonary vessels. 4 In patients, pulmonary hypertension secondary to chronic obstructive lung disease is associated with thickening of the intima of the pulmonary arteries. 5 Furthermore, the degree of intimal thickening is related to the severity of lung disease. 5 , 6 Endothelial cells release potent . . .