Regulation of the nitric oxide synthase-nitric oxide- cGMP pathway in rat mesenteric endothelial cells

2001 ◽  
Vol 91 (6) ◽  
pp. 2553-2560 ◽  
Author(s):  
Andreas Papapetropoulos ◽  
Stavroula Andreopoulos ◽  
Carolyn Y. Go ◽  
Azizul Hoque ◽  
Leslie C. Fuchs ◽  
...  

Most of the available data on the nitric oxide (NO) pathway in the vasculature is derived from studies performed with cells isolated from conduit arteries. We investigated the expression and regulation of components of the NO synthase (NOS)-NO-cGMP pathway in endothelial cells from the mesenteric vascular bed. Basally, or in response to bradykinin, cultured mesenteric endothelial cells (MEC) do not release NO and do not express endothelial NOS protein. MEC treated with cytokines, but not untreated cells, express inducible NOS (iNOS) mRNA and protein, increase nitrite release, and stimulate cGMP accumulation in reporter smooth muscle cells. Pretreatment of MEC with genistein abolished the cytokine-induced iNOS expression. On the other hand, exposure of MEC to the microtubule depolymerizing agent colchicine did not affect the cytokine-induced increase in nitrite formation and iNOS protein expression, whereas it inhibited the induction of iNOS in smooth muscle cells. Collectively, our findings demonstrate that MEC do not express endothelial NOS but respond to inflammatory stimuli by expressing iNOS, a process that is blocked by tyrosine kinase inhibition but not by microtubule depolymerization.

Author(s):  
Shengyu Chen ◽  
Jing Wang ◽  
Fan Jia ◽  
Zhi-da Shen ◽  
Wen-bin Wang ◽  
...  

Thrombus and restenosis after stent implantation are the major complications because of traditional drugs such as rapamycin delay the process of endothelialization. Nitric oxide (NO) is mainly produced by endothelial...


2003 ◽  
Vol 83 (1) ◽  
pp. 183-252 ◽  
Author(s):  
Giovanni E. Mann ◽  
David L. Yudilevich ◽  
Luis Sobrevia

While transport processes for amino acids and glucose have long been known to be expressed in the luminal and abluminal membranes of the endothelium comprising the blood-brain and blood-retinal barriers, it is only within the last decades that endothelial and smooth muscle cells derived from peripheral vascular beds have been recognized to rapidly transport and metabolize these nutrients. This review focuses principally on the mechanisms regulating amino acid and glucose transporters in vascular endothelial cells, although we also summarize recent advances in the understanding of the mechanisms controlling membrane transport activity and expression in vascular smooth muscle cells. We compare the specificity, ionic dependence, and kinetic properties of amino acid and glucose transport systems identified in endothelial cells derived from cerebral, retinal, and peripheral vascular beds and review the regulation of transport by vasoactive agonists, nitric oxide (NO), substrate deprivation, hypoxia, hyperglycemia, diabetes, insulin, steroid hormones, and development. In view of the importance of NO as a modulator of vascular tone under basal conditions and in disease and chronic inflammation, we critically review the evidence that transport of l-arginine and glucose in endothelial and smooth muscle cells is modulated by bacterial endotoxin, proinflammatory cytokines, and atherogenic lipids. The recent colocalization of the cationic amino acid transporter CAT-1 (system y+), nitric oxide synthase (eNOS), and caveolin-1 in endothelial plasmalemmal caveolae provides a novel mechanism for the regulation of NO production by l-arginine delivery and circulating hormones such insulin and 17β-estradiol.


1995 ◽  
Vol 308 (1) ◽  
pp. 231-236 ◽  
Author(s):  
W Durante ◽  
K Cheng ◽  
R K Sunahara ◽  
A I Schafer

Experiments were performed to examine the effect of ethanol on the production of nitric oxide from interleukin-1 beta (IL-1 beta)-treated cultured rat aortic smooth muscle cells. Incubation of vascular smooth muscle cells with IL-1 beta resulted in the release of nitrite and in the intracellular accumulation of L-citrulline. In parallel with this, IL-1 beta increased inducible nitric oxide synthase (iNOS) mRNA and protein. Ethanol (6.5-650 mM) potentiated the IL-1 beta-mediated stimulation of iNOS mRNA production, the appearance of iNOS protein and the generation of nitrite and L-citrulline from smooth muscle cells in a concentration-dependent manner. In the absence of IL-1 beta, ethanol failed to induce iNOS expression. These results demonstrate that pharmacologically relevant concentrations of ethanol enhance the IL-1 beta-induced expression of the iNOS gene in vascular smooth muscle. The ability of ethanol to augment the release of the platelet inhibitor and vasodilator nitric oxide may, in part, contribute to the beneficial cardiovascular effects associated with moderate alcohol consumption.


1999 ◽  
Vol 46 (3) ◽  
pp. 703-715 ◽  
Author(s):  
A Józkowicz ◽  
J Pankiewicz ◽  
J Dulak ◽  
L Partyka ◽  
I Wybrańska ◽  
...  

The regulation of vascular wall homeostasis by nitric oxide (NO) generated by endothelium is being intensively studied. In the present paper, the involvement of NO in the vascular endothelial growth factor (VEGF), insulin or leptin-stimulated proliferation of human endothelial cells (HUVEC) was measured by [3H]thymidine or bromodeoxyuridine incorporation. VEGF and insulin, but not leptin, increased NO generation in HUVEC, as detected with ISO-NO electrode. Proliferation of HUVEC induced by leptin was not changed or was higher in the presence of N(omega)-nitro-L-arginine methyl ester (L-NAME) a nitric oxide synthase (NOS) inhibitor. In contrast, L-NAME blunted the proproliferative effect of VEGF and insulin. Furthermore, we demonstrated that, in human arterial smooth muscle cells (hASMC) transfected with endothelial NOS (eNOS) gene, the generation of biologically active VEGF protein was NO-dependent. Inhibition of NO generation by L-NAME decreased the synthesis of VEGF protein and attenuated HUVEC proliferation induced by conditioned media from transfected hASMC. Endothelium-derived NO seems to participate in VEGF and insulin, but not leptin, mitogenic activity. Additionally, the small amounts of NO released from endothelial cells, as mimicked by eNOS transfection into hASMC, may activate generation of VEGF in sub-endothelial smooth muscle cells, leading to increased synthesis of VEGF protein necessary for turnover and restitution of endothelial cells.


2007 ◽  
Vol 292 (4) ◽  
pp. F1124-F1131 ◽  
Author(s):  
T. R. Uhrenholt ◽  
J. Schjerning ◽  
P. M. Vanhoutte ◽  
B. L. Jensen ◽  
O. Skøtt

Vasoconstriction and increase in the intracellular calcium concentration ([Ca2+]i) of vascular smooth muscle cells may cause an increase of endothelial cell [Ca2+]i, which, in turn, augments nitric oxide (NO) production and inhibits smooth muscle cell contraction. This hypothesis was tested in microperfused rabbit renal afferent arterioles, using fluorescence imaging microscopy with the calcium-sensitive dye fura-2 and the NO-sensitive dye 4-amino-5-methylamino-2′,7′-difluorescein. Both dyes were loaded into smooth muscle and endothelium. Depolarization with 100 mmol/l KCl led to a transient vasoconstriction which was converted into a sustained response by N-nitro-l-arginine methyl ester (l-NAME). Depolarization increased smooth muscle cell [Ca2+]ifrom 162 ± 15 nmol/l to a peak of 555 ± 70 nmol/l ( n = 7), and this response was inhibited by 80% by the l-type calcium channel blocker calciseptine. After a delay of 10 s, [Ca2+]iincreased in endothelial cells immediately adjacent to reactive smooth muscle cells, and this calcium wave spread in a nonregenerative fashion laterally into the endothelial cell layer with a velocity of 1.2 μm/s. Depolarization with 100 mmol/l KCl led to a significant increase in NO production ([NO]i) which was inhibited by l-NAME ( n = 5). Acetylcholine caused a rapid increase in endothelial [Ca2+]i, which did not transfer to the smooth muscle cells. l-NAME treatment did not affect changes in smooth muscle [Ca2+]iafter depolarization, but it did increase the calcium sensitivity of the contractile apparatus. We conclude that depolarization increases smooth muscle [Ca2+]iwhich is transferred to the endothelial cells and stimulates NO production which curtails vasoconstriction by reducing the calcium sensitivity of the contractile apparatus.


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