[Regulation of pulmonary circulation by the vascular endothelium]

The function of the endothelial mediators on lung vessels is progressively understood. Our experimental results, in agreement with those from other laboratories, show that prostacyclin and nitric oxide do not affect basal pulmonary vascular tone, but that they limit the pulmonary hypertension secondary to alveolar hypoxia, or to lung injury. The role of endothelins remains harder to define, partly because their vascular effects are opposed by nitric oxide in intact animals.