Neuropeptide Y stimulates DNA synthesis in human vascular smooth muscle cells through neuropeptide Y Y1 receptors

2000 ◽  
Vol 78 (3) ◽  
pp. 256-259 ◽  
Author(s):  
T Nilsson ◽  
L Edvinsson

We investigated the mitogenic effect, measured as [3H]thymidine incorporation, of neuropeptide Y (NPY) on smooth muscle cells (SMCs) from human subcutaneous arteries (diameter: 0.4 mm). NPY stimulated DNA synthesis in a concentration-dependent manner, Emax 32 ± 5% relative to control. The effect was potently antagonised by the NPY Y1 receptor antagonist BIBP3226 ((R)-N2-(diphenylacetyl)-N-[(4-hydroxy-phenyl)methyl]-D-arginine-amide), indicating the effect to be mediated via the NPY Y1 receptor. Noradrenaline (NA) also induced mitogenesis, Emax 35 ± 10% relative to control. When added together, NPY and NA potentiated the [3H]thymidine incorporation, Emax 109 ± 38% relative to control. Also, this effect seems to be mediated by the NPY Y1 receptor, since BIBP3226 blocked the effect (44 ± 9% relative to control). The mitogenic effect of NPY and NA, two important transmitters of the sympathetic nervous system, might have clinical consequences on conditions with elevated sympathetic nerve activity.Key words: BIBP3226, mitogenesis, neuropeptide Y, vascular smooth muscle cells.

1991 ◽  
Vol 260 (5) ◽  
pp. H1713-H1717 ◽  
Author(s):  
U. Ikeda ◽  
M. Ikeda ◽  
T. Oohara ◽  
A. Oguchi ◽  
T. Kamitani ◽  
...  

We have investigated the effect of interleukin 6 (IL-6) on the growth of vascular smooth muscle cells (VSMC) isolated from rat aortas. Murine recombinant IL-6 significantly increased the number of VSMC and stimulated tritiated thymidine incorporation into VSMC in a dose-dependent manner. The IL-6-induced thymidine incorporation into VSMC was totally inhibited by the Ca2+ channel blocker verapamil; however, IL-6 showed no effects on the intracellular Ca2+ level ([Ca2+]i) in VSMC. Antibody against platelet-derived growth factor (PDGF) also totally inhibited the IL-6-induced thymidine uptake. PDGF caused a significant increase in the [Ca2+]i, which was totally inhibited by verapamil. IL-6 mRNA was not detected in unstimulated “quiescent” VSMC, but its expression was stimulated by exposure of VSMC to 10% fetal bovine serum. Immunohistochemical study using anti-PDGF antibody showed that IL-6 stimulated PDGF production in VSMC. These results support the premise that IL-6 is released by VSMC in an autocrine manner and promotes the growth of VSMC via induction of endogenous PDGF production.


Peptides ◽  
1993 ◽  
Vol 14 (2) ◽  
pp. 263-268 ◽  
Author(s):  
Zofia Zukowska-Grojec ◽  
Piotr Pruszczyk ◽  
Carol Colton ◽  
Jibin Yao ◽  
Gregory H. Shen ◽  
...  

1984 ◽  
Vol 247 (5) ◽  
pp. C501-C505 ◽  
Author(s):  
N. E. Owen

Platelet-derived growth factor (PDGF) is known to be a potent mitogenic agent for vascular smooth muscle cells. The effect of PDGF on amiloride-sensitive Na+ influx was investigated in A-10 vascular smooth muscle cells. At a dose which maximally stimulates DNA synthesis, PDGF stimulates net Na+ influx in vascular smooth muscle cells. The PDGF-stimulated Na+ influx is linear over a 5-min time course. PDGF stimulates Na+ influx in a concentration-dependent manner, with a concentration of 0.5 U/ml causing half-maximal inhibition. The effects of PDGF on Na+ influx can be mimicked by 10% fetal bovine serum or by the divalent cation ionophore A23187 (5 microM). Net Na+ influx in response to each of these agents was inhibited by amiloride and by benzamil. PDGF-stimulated net Na+ influx was blocked by the intracellular Ca2+ antagonist 8-(N,N-diethylamino)-octyl-3,4,5-trimethoxybenzoate as well as by the calmodulin antagonists trifluoperazine, chlorpromazine, and imipramine. These data suggest that PDGF may stimulate an amiloride-sensitive Na+ influx pathway via an elevation in intracellular Ca2+ and formation of a Ca-calmodulin complex. This Na+ influx pathway may be a trigger for PDGF-stimulated DNA synthesis.


1997 ◽  
Vol 273 (2) ◽  
pp. H628-H633 ◽  
Author(s):  
J. W. Gu ◽  
T. H. Adair

We determined whether hypoxia-induced expression of vascular endothelial growth factor (VEGF) can be reversed by a normoxic environment. Dog myocardial vascular smooth muscle cells (MVSMCs) were exposed to hypoxia (1% O2) for 24 h and then returned to normoxia (20% O2). VEGF protein levels increased by more than fivefold after 24 h of hypoxia and returned to baseline within 24 h of the return of the cells to normoxia. Northern blot analysis showed that hypoxia caused a 5.5-fold increase in VEGF mRNA, and, again, the expression was reversed after reinstitution of normoxia. Additional measurements showed that basic fibroblast growth factor and platelet-derived growth factor protein levels were not induced by hypoxia and that hypoxia caused a fourfold decrease in transforming growth factor-beta 1 protein levels. Hypoxia conditioned media from MVSMCs caused human umbilical vein endothelial cells to increase [3H]thymidine incorporation by twofold, an effect that was blocked in a dose-dependent manner by anti-human VEGF antibody. The hypoxia conditioned media had no effect on MVSMC proliferation. These findings suggest that VEGF expression can be bidirectionally controlled by tissue oxygenation, and thus support the hypothesis that VEGF is a physiological regulator of angiogenesis.


2000 ◽  
Vol 78 (2) ◽  
pp. 162-172 ◽  
Author(s):  
Danielle Jacques ◽  
Sawsan Sader ◽  
Nesrine El-Bizri ◽  
Sanaa Chouffani ◽  
Ghada Hassan ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document