title: Differential regulation of diverse physiological responses to VEGF in pulmonary endothelial cells.
abstract: The mechanisms responsible for the divergent physiological responses of endothelial cells to vascular endothelial growth factor (VEGF) are incompletely understood. We hypothesized that VEGF elicits increased endothelial permeability and cell migration via differential activation of intracellular signal transduction pathways. To test this hypothesis, we established a model of VEGF-induced endothelial barrier dysfunction and chemotaxis with bovine pulmonary endothelial cells. We compared the effects of VEGF on transendothelial electrical resistance (TER), actin cytoskeletal remodeling, and chemotaxis of lung endothelial cells and then evaluated the role of the mitogen-activated protein kinases (MAPKs) p38 and extracellular signal-regulated kinase (ERK)1/2 in VEGF-mediated endothelial responses. The dose response of pulmonary arterial and lung microvascular endothelial cells to VEGF differed when barrier regulation and chemotaxis were evaluated. Inhibition of tyrosine kinase, phosphoinositol 3-kinase, or p38 MAPK significantly attenuated VEGF-mediated TER, F-actin remodeling, and chemotaxis. VEGF-mediated decreased TER was also significantly attenuated by inhibition of ERK1/2 MAPK but not by inhibition of fetal liver kinase-1 (flk-1) or Src kinase. In contrast, VEGF-mediated endothelial migration was not attenuated by ERK1/2 inhibition but was abolished by inhibition of either flk-1 or Src kinase. These data suggest potential mechanisms by which VEGF may differentially mediate physiological responses in vivo.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21224-6801, USA. pbecker@mail.jhmi.edu
authors.forename: P M
authors.initials: PM
authors.lastname: Becker
authors.forename: A D
authors.initials: AD
authors.lastname: Verin
authors.forename: M A
authors.initials: MA
authors.lastname: Booth
authors.forename: F
authors.initials: F
authors.lastname: Liu
authors.forename: A
authors.initials: A
authors.lastname: Birukova
authors.forename: J G
authors.initials: JG
authors.lastname: Garcia
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D002070:Butadienes / Q000494:pharmacology; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002463:Cell Membrane Permeability / Q000187:drug effects; D002478:Cells, Cultured; D002633:Chemotaxis / Q000187:drug effects; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D016228:Endothelial Growth Factors / Q000494:pharmacology*; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D004789:Enzyme Activation / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D066298:In Vitro Techniques; D008222:Lymphokines / Q000494:pharmacology*; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D009570:Nitriles / Q000494:pharmacology; D011651:Pulmonary Artery / Q000166:cytology*; D011725:Pyridines / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D017978:Receptors, Growth Factor / Q000037:antagonists & inhibitors / Q000378:metabolism; D040262:Receptors, Vascular Endothelial Growth Factor; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D048051:p38 Mitogen-Activated Protein Kinases; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: C412373:AG 1879; D000199:Actins; D002070:Butadienes; D016228:Endothelial Growth Factors; D004791:Enzyme Inhibitors; D007093:Imidazoles; D008222:Lymphokines; D009570:Nitriles; D011725:Pyridines; D011743:Pyrimidines; D017978:Receptors, Growth Factor; C113580:U 0126; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D020794:Receptor Protein-Tyrosine Kinases; D040262:Receptors, Vascular Endothelial Growth Factor; D019061:src-Family Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C090942:4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)imidazole