Plasma endothelin-1 concentrations in patients with Behçet's disease.

Plasma Endothelin-1 (ET-1) concentrations were determined by radio immunoassay in 30 patients with Behçet's disease at various stages and 20 healthy subjects. Mean ET-1 plasma concentrations were significantly (p < 0.001) increased in patients with active Behçet's disease (35.99 +/- 5.06 fmol/ml, mean +/- standard error) compared to concentrations found in healthy volunteers (10.98 +/- 0.84 fmol/ml). No difference in plasma ET-1 level was observed between patients with inactive Behçet's disease (12.98 +/- 1.14 fmol/ml) and volunteers. Increased plasma levels of ET-1 in patients with Behçet's disease may be attributable to increased secretion or leakage of this mitogen from injured vascular endothelial cells. These results indicate that ET-1 may play an important pathogenetic role in the development or progression of vasculitis common to Behçet's disease. Plasma concentrations of ET-1 correlates with the activity of illness.