title: Src kinase mediates angiotensin II-dependent increase in pulmonary endothelial nitric oxide synthase.
abstract: We have previously demonstrated that angiotensin II (Ang II) stimulates nitric oxide (NO) production in bovine pulmonary artery endothelial cells (BPAECs) by increasing NO synthase (NOS) expression via the type 2 receptor. The purpose of this study was to identify the Ang II-dependent signaling pathway that mediates this increase in endothelial NOS (eNOS). The Ang II-dependent increase in eNOS expression is prevented when BPAECs are pretreated with the tyrosine kinase inhibitors, herbimycin A and 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-D]pyrimidine, which also blocked Ang II-dependent mitogen-activated protein kinase (MAPK) kinase/extracellular-regulated protein kinase (MEK)-1 and MAPK phosphorylation, suggesting that Src is upstream of MAPK in this pathway. Transfection of BPAECs with an Src dominant negative mutant cDNA prevented the Ang II-dependent Src activation and increase in eNOS protein expression. PD98059, a MEK-1 inhibitor, prevented the Ang II-dependent phosphorylation of extracellular-regulated protein kinases 1 and 2 and increase in eNOS expression. Neither AG1478, an epidermal growth factor receptor kinase inhibitor, nor AG1295, a platelet derived growth factor receptor kinase inhibitor, had any effect on Ang II-stimulated Src activity, MAPK activation, or eNOS expression. Pertussis toxin prevented the Ang II-dependent increase in Src activity, MAPK activation, and eNOS expression. These data suggest that Ang II stimulates Src tyrosine kinase via a pertussis toxin-sensitive pathway, which in turn activates the MAPK pathway, resulting in increased eNOS protein expression in BPAECs.
authors.affiliation: Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595, USA.
authors.forename: Xinmei
authors.initials: X
authors.lastname: Li
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Lerea
authors.forename: Jianyu
authors.initials: J
authors.lastname: Li
authors.forename: Susan C
authors.initials: SC
authors.lastname: Olson
mesh_terms: D000804:Angiotensin II / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D048369:MAP Kinase Kinase 1; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000187:drug effects / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III; D037342:Pertussis Toxin / Q000494:pharmacology; D011651:Pulmonary Artery / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D004791:Enzyme Inhibitors; D000804:Angiotensin II; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; D037342:Pertussis Toxin; D019061:src-Family Kinases; D020928:Mitogen-Activated Protein Kinases; D048369:MAP Kinase Kinase 1; D020929:Mitogen-Activated Protein Kinase Kinases