PMID- 18816248 OWN - NLM STAT- MEDLINE DCOM- 20090115 LR - 20181113 IS - 1470-8728 (Electronic) IS - 0264-6021 (Print) IS - 0264-6021 (Linking) VI - 417 IP - 2 DP - 2009 Jan 15 TI - Vascular endothelial growth factor acts through novel, pregnancy-enhanced receptor signalling pathways to stimulate endothelial nitric oxide synthase activity in uterine artery endothelial cells. PG - 501-11 LID - 10.1042/BJ20081013 [doi] AB - During pregnancy, VEGF (vascular endothelial growth factor) regulates in part endothelial angiogenesis and vasodilation. In the present study we examine the relative roles of VEGFRs (VEGF receptors) and associated signalling pathways mediating the effects of VEGF(165) on eNOS (endothelial nitric oxide synthase) activation. Despite equal expression levels of VEGFR-1 and VEGFR-2 in UAECs (uterine artery endothelial cells) from NP (non-pregnant) and P (pregnant) sheep, VEGF(165) activates eNOS at a greater level in P- compared with NP-UAEC, independently of Akt activation. The selective VEGFR-1 agonist PlGF (placental growth factor)-1 elicits only a modest activation of eNOS in P-UAECs compared with VEGF(165), whereas the VEGFR-2 kinase inhibitor blocks VEGF(165)-stimulated eNOS activation, suggesting VEGF(165) predominantly activates eNOS via VEGFR-2. Although VEGF(165) also activates ERK (extracellular-signal-regulated kinase)-1/2, this is not necessary for eNOS activation since U0126 blocks ERK-1/2 phosphorylation, but not eNOS activation, and the VEGFR-2 kinase inhibitor inhibits eNOS activation, but not ERK-1/2 phosphorylation. Furthermore, the inability of PlGF to activate ERK-1/2 and the ability of the VEGFR-2 selective agonist VEGF-E to activate ERK-1/2 and eNOS suggests again that both eNOS and ERK-1/2 activation occur predominantly via VEGFR-2. The lack of VEGF(165)-stimulated Akt phosphorylation is consistent with a lack of robust phosphorylation of Ser(1179)-eNOS. Although VEGF(165)-stimulated eNOS phosphorylation is observed at Ser(617) and Ser(635), pregnancy does not significantly alter this response. Our finding that VEGF(165) activation of eNOS is completely inhibited by wortmannin but not LY294002 implies a downstream kinase, possibly a wortmannin-selective PI3K (phosphoinositide 3-kinase), is acting between the VEGFR-2 and eNOS independently of Akt. FAU - Grummer, Mary A AU - Grummer MA AD - Department of Obstetrics & Gynecology, Perinatal Research Laboratories, University of Wisconsin, Madison, WI 53715, U.S.A. FAU - Sullivan, Jeremy A AU - Sullivan JA FAU - Magness, Ronald R AU - Magness RR FAU - Bird, Ian M AU - Bird IM LA - eng GR - R01 HL049210/HL/NHLBI NIH HHS/United States GR - R01 HL079020-02/HL/NHLBI NIH HHS/United States GR - HD 38843/HD/NICHD NIH HHS/United States GR - HL 64601/HL/NHLBI NIH HHS/United States GR - P01 HD038843-07/HD/NICHD NIH HHS/United States GR - R01 HL064601-01A1/HL/NHLBI NIH HHS/United States GR - P01 HD038843-04S1/HD/NICHD NIH HHS/United States GR - R01 HL049210-03S1/HL/NHLBI NIH HHS/United States GR - P01 HD038843-03/HD/NICHD NIH HHS/United States GR - HL 079020/HL/NHLBI NIH HHS/United States GR - R01 HL049210-06/HL/NHLBI NIH HHS/United States GR - P01 HD038843-01A10002/HD/NICHD NIH HHS/United States GR - P01 HD038843-03S1/HD/NICHD NIH HHS/United States GR - P01 HD038843-06A10002/HD/NICHD NIH HHS/United States GR - P01 HD038843-01A1/HD/NICHD NIH HHS/United States GR - R01 HL049210-05A2/HL/NHLBI NIH HHS/United States GR - HL 49210/HL/NHLBI NIH HHS/United States GR - R01 HL049210-03/HL/NHLBI NIH HHS/United States GR - R01 HL049210-07/HL/NHLBI NIH HHS/United States GR - R01 HL064601/HL/NHLBI NIH HHS/United States GR - R01 HL049210-09A1/HL/NHLBI NIH HHS/United States GR - R01 HL049210-10/HL/NHLBI NIH HHS/United States GR - P01 HD038843-079001/HD/NICHD NIH HHS/United States GR - P01 HD038843-06A1/HD/NICHD NIH HHS/United States GR - R01 HL064601-02/HL/NHLBI NIH HHS/United States GR - P01 HD038843-02/HD/NICHD NIH HHS/United States GR - R01 HL079020-01A2/HL/NHLBI NIH HHS/United States GR - P01 HD038843-06A19001/HD/NICHD NIH HHS/United States GR - P01 HD038843-070002/HD/NICHD NIH HHS/United States GR - R01 HL064601-03/HL/NHLBI NIH HHS/United States GR - P01 HD038843-04S2/HD/NICHD NIH HHS/United States GR - P01 HD038843-05/HD/NICHD NIH HHS/United States GR - P01 HD038843-05S1/HD/NICHD NIH HHS/United States GR - P01 HD038843-020002/HD/NICHD NIH HHS/United States GR - R01 HL049210-08/HL/NHLBI NIH HHS/United States GR - R01 HL064601-04/HL/NHLBI NIH HHS/United States GR - P01 HD038843-04/HD/NICHD NIH HHS/United States GR - R01 HL049210-05A2S1/HL/NHLBI NIH HHS/United States GR - R01 HL079020/HL/NHLBI NIH HHS/United States GR - P01 HD038843/HD/NICHD NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural PL - England TA - Biochem J JT - The Biochemical journal JID - 2984726R RN - 0 (Vascular Endothelial Growth Factor A) RN - EC 1.14.13.39 (Nitric Oxide Synthase Type III) RN - EC 2.7.10.1 (Vascular Endothelial Growth Factor Receptor-1) RN - EC 2.7.10.1 (Vascular Endothelial Growth Factor Receptor-2) SB - IM MH - Animals MH - Arteries/drug effects/*metabolism MH - Cells, Cultured MH - Endothelial Cells/drug effects/*metabolism MH - Female MH - Nitric Oxide Synthase Type III/*metabolism MH - Phosphorylation MH - Pregnancy MH - Sheep MH - Signal Transduction MH - Uterus/drug effects/*metabolism MH - Vascular Endothelial Growth Factor A/*pharmacology MH - Vascular Endothelial Growth Factor Receptor-1/*metabolism MH - Vascular Endothelial Growth Factor Receptor-2/*metabolism PMC - PMC2680709 MID - NIHMS77243 EDAT- 2008/09/26 09:00 MHDA- 2009/01/16 09:00 PMCR- 2010/01/15 CRDT- 2008/09/26 09:00 PHST- 2008/09/26 09:00 [pubmed] PHST- 2009/01/16 09:00 [medline] PHST- 2008/09/26 09:00 [entrez] PHST- 2010/01/15 00:00 [pmc-release] AID - BJ20081013 [pii] AID - 10.1042/BJ20081013 [doi] PST - ppublish SO - Biochem J. 2009 Jan 15;417(2):501-11. doi: 10.1042/BJ20081013.