Endothelin-1 in acute lung injury and the adult respiratory distress syndrome.

Endothelial damage is a hallmark of acute lung injury. Endothelial mediators may increase pulmonary vascular tone and induce pulmonary arterial muscularization, thereby contributing to the pulmonary hypertension seen with acute lung injury. We measured plasma levels and net pulmonary clearance of endothelin-1, a potent endothelium-derived vasoconstrictor peptide and smooth muscle mitogen, in 26 patients with early acute lung injury, the adult respiratory distress syndrome, and pulmonary hypertension. Nineteen had another data collection at clinical improvement or worsening. Control subjects (n = 25) had no pulmonary hypertension or lung injury. Initial mixed venous and systemic arterial plasma endothelin-1 levels were elevated (4.6 ± 0.6 SEM and 4.9 ± 0.6 pg/ml, respectively) as compared with control subjects (0.9 ± 0.1 and 0.6 ± 0.1 pg/ml). The systemic arterial/venous endothelin-1 ratio was 1.1 ± 0.1 (0.7 ± 0.1 in control subjects), indicating a reduction in normal net pulmonary endothelin-1 clearance. ...