Nitric Oxide Induces the Synthesis of Vascular Endothelial Growth Factor by Rat Vascular Smooth Muscle Cells

• Published in: Arteriosclerosis, thrombosis, and vascular biology Vol. 20; no. 3; pp. 659 - 666
• Main Authors: Dulak, Józef, Józkowicz, Alicja, Dembinska-Kiec, Aldona, Guevara, Ibeth, Zdzienicka, Anna, Zmudzinska-Grochot, Danuta, Florek, Izabela, Wójtowicz, Anna, Szuba, Andrzej, Cooke, John P
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA American Heart Association, Inc 01.03.2000; Hagerstown, MD Lippincott
• Subjects: Animals; Antioxidants - pharmacology; Arteriosclerosis - metabolism; Atherosclerosis (general aspects, experimental research); Biological and medical sciences; Biopterins - analogs & derivatives; Biopterins - pharmacology; Blood and lymphatic vessels; Cardiology. Vascular system; Cells, Cultured; DNA Primers; Endothelial Growth Factors - genetics; Enzyme Inhibitors - pharmacology; Ferrocyanides - pharmacology; Gene Expression Regulation, Enzymologic - drug effects; Gene Expression Regulation, Enzymologic - physiology; Interleukin-1 - pharmacology; Lymphokines - genetics; Medical sciences; Muscle, Smooth, Vascular - cytology; Muscle, Smooth, Vascular - metabolism; NG-Nitroarginine Methyl Ester - pharmacology; Nitric Oxide - metabolism; Nitric Oxide Donors - pharmacology; Nitric Oxide Synthase - antagonists & inhibitors; Nitric Oxide Synthase - genetics; Nitric Oxide Synthase Type II; Nitroprusside - pharmacology; Rats; RNA, Messenger - analysis; Thoracic Arteries - cytology; Transfection; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors; Vasodilator Agents - pharmacology; Cell culture; Rat; Pathogenesis; Rodentia; Cardiovascular disease; Smooth muscle; Vascular disease; Vertebrata; Mammalia; Vascular endothelium growth factor; Animal; Nitric oxide; Blood vessel; Atherosclerosis
• ISSN: 1079-5642; 1524-4636
• DOI: 10.1161/01.atv.20.3.659

ABSTRACTVascular endothelial growth factor (VEGF) is known to induce the release of nitric oxide (NO) from endothelial cells. However, the effect of NO on VEGF synthesis is not clear. Accordingly, the effect of endogenous and exogenous NO on VEGF synthesis by rat vascular smooth muscle cells (VSMCs) was investigated. Two in vitro models were used(1) VSMCs stimulated to produce NO by treatment with interleukin (IL)-1β (10 ng/mL) and (2) VSMCs lipotransfected with pKecNOS plasmid, containing the endothelial constitutive NO synthase (ecNOS) cDNA. The synthesis of NO was inhibited by N-nitro-L-arginine methyl ester (L-NAME, 2 to 5 mmol/L) or diaminohydroxypyrimidine (DAHP, 2.5 to 5 mmol/L), inhibitors of NOS and GTP cyclohydrolase I, respectively. Some cells treated with L-NAME or DAHP were supplemented with L-arginine (10 mmol/L) or tetrahydrobiopterin (BH4; 100 μmol/L), respectively. In addition, we studied the effect of sodium nitroprusside (SNP; 10 and 100 μmol/L) and chemically related compounds, potassium ferrocyanide and ferricyanide, on VEGF generation. IL-1β induced iNOS expression and NO generation and significantly upregulated VEGF mRNA expression and protein synthesis. L-NAME and DAHP totally inhibited NO generation and decreased the IL-1β–upregulated VEGF synthesis by 30% to 40%. Supplementation with L-arginine or BH4 increased NO generation by L-NAME– or DAHP-treated cells, and VEGF synthesis was augmented by addition of BH4. The cells generating NO after pKecNOS transfection released significantly higher amounts of VEGF than cells transfected with control plasmids. Inhibition of NO generation by L-NAME decreased VEGF synthesis. In contrast to the effect of endogenous NO, we observed the inhibition of VEGF synthesis in the presence of high (10 or 100 μmol/L) concentrations of SNP. This effect was mimicked by chemically related ferricyanide and ferrocyanide compounds, suggesting that the inhibitory effect of sodium nitroprusside may be mediated by an NO-independent mechanism. The results indicate that endogenous NO enhances VEGF synthesis. The positive interaction between endogenous NO and VEGF may have implications for endothelial regeneration after balloon angioplasty and for angiogenesis.