EN
The vascular endothelium is not merely a passive physical barrier between blood and tissues, but may actively modulate the tone of blood vessels. Under certain conditions endothelial cells have been shown to produce powerful vasodilators (endothelium-derived relaxing factor - EDRF - and prostacyclin) or vasoconstrictor(s) (endothelium-derived constricting factor - EDCF) [for review see: Griffith et al., 1988; Vanhoutte and Katusic, 1988]. In contrast to the extensive studies performed to characterize the actions and nature of EDRF, recently identified as nitric oxide [for review see: Moncada et al., 1988], relatively little is known about EDCF(s). This paper reviews recent data on EDCF and a special emphasis is put on a newly discovered vasoconstricting peptide, endothelin.