Vascular endothelial growth factor A, long form
positive regulation of endothelial cell proliferation
Vasoactive peptides modulate vascular endothelial cell growth factor production and endothelial cell proliferation and invasion.
The proliferation of vascular endothelial cells (EC) is an important event in angiogenesis. The synthesis of the EC growth factor, vascular endothelial cell growth factor (VEGF), is stimulated by a variety of activators; but the effects of important vasoactive peptides are not well understood, and there are no known natural inhibitors of VEGF production. We found that the vasoactive peptides endothelin (ET)-1 and ET-3 stimulated the synthesis of VEGF protein 3-4-fold in cultured human vascular smooth muscle cells, comparable in magnitude to hypoxia. ET-1 and ET-3 acted through the ETA and ETB receptors, respectively, and signaling through protein kinase C was important. Atrial natriuretic peptide (ANP), C-type natriuretic peptide, and C-ANP-(4-23), a ligand for the natriuretic peptide clearance receptor, equipotently inhibited production of VEGF by as much as 88% and inhibited ET- or hypoxia-stimulated VEGF transcription. EC proliferation and invasion of matrix were stimulated by VEGF secreted into the medium by ET-incubated vascular smooth muscle cells. This was inhibited by ANP. Our results identify the natriuretic peptides as the first peptide inhibitors of VEGF synthesis and indicate a novel mechanism by which vasoactive peptides could modulate angiogenesis.