Immediate and delayed VEGF‐mediated NO synthesis in endothelial cells: Role of PI3K, PKC and PLC pathways

• Published in: British journal of pharmacology 2002-12, Vol.137 (7), p.1021-1030
• Main Authors: Gélinas, David S, Bernatchez, Pascal N, Rollin, Simon, Bazan, Nicolas G, Sirois, Martin G
• Format: Article
• Language: English
• Subjects: 1-Methyl-3-isobutylxanthine - pharmacology; Androstadienes - pharmacology; Animals; Biological and medical sciences; Blood vessels and receptors; Calcimycin - pharmacology; Calcium - antagonists & inhibitors; Cattle; Cells, Cultured; Chelating Agents - pharmacology; Chromones - pharmacology; Cyclic GMP - metabolism; Diterpenes; Dose-Response Relationship, Drug; Egtazic Acid - analogs & derivatives; Egtazic Acid - pharmacology; Endothelial Growth Factors - pharmacology; Endothelium, Vascular - cytology; Endothelium, Vascular - drug effects; Endothelium, Vascular - metabolism; eNOS; Enzyme Inhibitors - pharmacology; Fundamental and applied biological sciences. Psychology; Ginkgolides; Indoles - pharmacology; Intercellular Signaling Peptides and Proteins - pharmacology; Ionophores - pharmacology; Lactones - pharmacology; Lymphokines - pharmacology; Maleimides - pharmacology; Medicin och hälsovetenskap; Morpholines - pharmacology; NG-Nitroarginine Methyl Ester - pharmacology; Nitric Oxide - metabolism; Nitric Oxide Donors - pharmacology; Nitric Oxide Synthase - antagonists & inhibitors; Nitric Oxide Synthase - metabolism; Nitric Oxide Synthase Type III; Nitroprusside - pharmacology; PAF; Phosphatidylinositol 3-Kinases - antagonists & inhibitors; Phosphatidylinositol 3-Kinases - metabolism; Phosphorylation - drug effects; PI3K; PKC; PLA2; Platelet Activating Factor - metabolism; Platelet Activating Factor - pharmacology; Platelet Membrane Glycoproteins - antagonists & inhibitors; PLC; Protein Kinase C - antagonists & inhibitors; Protein Kinase C - metabolism; Protein-Serine-Threonine Kinases; Proto-Oncogene Proteins - metabolism; Proto-Oncogene Proteins c-akt; Receptors, Cell Surface - antagonists & inhibitors; Receptors, G-Protein-Coupled; Serine - metabolism; Signal Transduction - physiology; Time Factors; Type C Phospholipases - antagonists & inhibitors; Type C Phospholipases - metabolism; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors; VEGF; Vertebrates: cardiovascular system
• ISSN: 0007-1188; 1476-5381
• DOI: 10.1038/sj.bjp.0704956

The mechanism(s) by which vascular endothelial growth factor (VEGF) induces endothelial nitric oxide synthase (eNOS) activation remain(s) unclear up to a certain extent. Therefore, we sought to evaluate the contribution of numerous pathways in VEGF‐induced nitric oxide (NO) synthesis by measuring cGMP production. In addition, as VEGF induces the synthesis of NO and platelet‐activating factor (PAF), we wanted to assess if the induction of PAF and NO is contributing to the synthesis of each other. Herein, we show that a treatment of endothelial cells with a phospholipase C (PLC) inhibitor (U73122), a calmodulin antagonist (W‐7) or with intracellular calcium chelators (EGTA/AM, BAPTA/AM) prevented VEGF‐mediated eNOS Ser1177‐phosphorylation and NO synthesis measured by cGMP production. Pretreatment with phosphatidylinositol 3‐kinase (PI3K) (Wortmannin, LY294002) or protein kinase C (PKC) (GF109203X, Ro318220) inhibitors attenuated eNOS Ser1177‐phosphorylation mediated by VEGF, but did not alter immediate (0–10 min) cGMP synthesis induced by VEGF, but abrogated by up to 84% the delayed (10–30 min) cGMP synthesis. Pretreatment with PAF synthesis inhibitors or with PAF receptor antagonists did not abrogate neither eNOS Ser1177‐phosphorylation nor cGMP synthesis mediated by VEGF. In conclusion, VEGF induces an immediate cGMP synthesis through the PLC‐Ca2+/CaM pathway, and that the induction of delayed cGMP synthesis implies Akt and PKC activity. British Journal of Pharmacology (2002) 137, 1021–1030. doi:10.1038/sj.bjp.0704956