Endothelin-converting enzyme-1 (ECE-1) is a key enzyme in endothelin processing. Although it has been revealed that ECE-1 expression increases in vascular wall after balloon injury in vivo experimental models, the regulation of ECE-1 expression in vitro remains undefined. In this study, we demonstrated that the endothelial cell-specific mitogen, vascular endothelial growth factor (VEGF) increased ECE-1 expression in cultured bovine aortic endothelial cells (BAEC). Northern blot analysis revealed that VEGF increased ECE-1 mRNA expression in 12-24 hours by 2-fold in BAEC, and this effect was dose-dependent. VEGF also increased ECE-1 protein expression detected by immunoblotting in 36 hours in BAEC. Therefore, VEGF increased ECE-1 expression in BAEC, which suggests that ECE-1 induction by VEGF may be involved in endothelin-system upregulation under pathological conditions such as neointimal formation and atherosclerosis.