title: Aortic endothelial cells synthesize basic fibroblast growth factor which remains cell associated and platelet-derived growth factor-like protein which is secreted.
abstract: Cultured bovine aortic endothelial cells synthesize growth factors which markedly differ in the regulation of their storage and secretion. Endothelial cell lysates, but not conditioned medium, contain a growth factor activity that appears to be basic fibroblast growth factor (FGF) by the following criteria: (1) it elutes from heparin-Sepharose at 1.4-1.6 M NaCl; (2) it is mitogenic for bovine aortic and capillary endothelial cells; (3) it is heat sensitive but stable to dithiothreitol; (4) it has a molecular weight of about 18,000 daltons; and (5) it cross-reacts with antiserum directed against basic FGF. In contrast, endothelial cell conditioned medium, but not lysates, contains a growth factor activity that (1) elutes from heparin-Sepharose at 0.4-0.5 M NaCl; (2) is mitogenic for fibroblasts and vascular smooth muscle cells but not for capillary endothelial cells; (3) is heat stable and dithiothreitol sensitive; and (4) competes with platelet-derived growth factor (PDGF) for binding to fibroblasts. From these criteria, it appears that endothelial cells secrete into the medium growth factors some of which are PDGF-like, but secrete little if any basic FGF. It is suggested that endothelial cell-associated basic FGF acts in an autocrine fashion to stimulate endothelial cell proliferation in response to endothelial cell perturbation or injury. On the other hand, the endothelial cell-secreted growth factors which are smooth muscle cell but not endothelial cell mitogens might exert a paracrine function on neighboring cells of the vessel wall.
mesh_terms: D000818:Animals; D001011:Aorta; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003470:Culture Media / Q000032:analysis; D004727:Endothelium / Q000378:metabolism*; D005346:Fibroblast Growth Factors / Q000096:biosynthesis*; D005347:Fibroblasts / Q000187:drug effects; D010982:Platelet-Derived Growth Factor / Q000096:biosynthesis* / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D003470:Culture Media; D010982:Platelet-Derived Growth Factor; D005346:Fibroblast Growth Factors