Abstract | BACKGROUND: METHODS AND RESULTS: This study used a silicone collar placed around rabbit carotid arteries to induce vascular injury and intimal thickening. Collar placement caused rapid upregulation of P2Y2 receptor mRNA in medial SMCs before appearance of neointima. Fura-2 digital imaging of single SMCs was used to measure changes in myoplasmic calcium concentration (Ca(m)) in response to P2Y receptor agonists. In contrast to UDP, activation by UTP or adenosine 5'-triphosphate ( ATP) greatly increased Ca(m), which indicates upregulation of functional P2Y2 receptors at which UTP and ATP are equipotent agonists. The number of responsive cells was significantly greater for freshly dispersed SMCs from collared arteries than for controls. Perivascular infusion of UTP (100 micromol/L) within the collar significantly enhanced neointimal development. Intimas that resulted from UTP exposure were infiltrated by macrophages. Moreover, increased expression of osteopontin occurred in response to in situ application of UTP. ATP or UTP also stimulated osteopontin expression in cultured SMCs in a dose-dependent manner. Furthermore, P2Y2 antisense oligonucleotide inhibited osteopontin expression induced by UTP. CONCLUSIONS:
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Authors | Cheikh I Seye, Qiongman Kong, Laurie Erb, Richard C Garrad, Brent Krugh, Meifang Wang, John T Turner, Michael Sturek, Fernando A González, Gary A Weisman |
Journal | Circulation
(Circulation)
Vol. 106
Issue 21
Pg. 2720-6
(Nov 19 2002)
ISSN: 1524-4539 [Electronic] United States |
PMID | 12438299
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Fluorescent Dyes
- P2ry2 protein, rat
- Receptors, Purinergic P2
- Receptors, Purinergic P2Y2
- Sialoglycoproteins
- Spp1 protein, rat
- purinoceptor P2Y4
- purinoceptor P2Y6
- Osteopontin
- RNA
- Adenosine Triphosphate
- Calcium
- Uridine Triphosphate
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Topics |
- Adenosine Triphosphate
(pharmacology)
- Animals
- Calcium
(metabolism)
- Carotid Arteries
(drug effects, metabolism, pathology)
- Carotid Stenosis
(chemically induced, metabolism, pathology)
- Cell Division
(drug effects)
- Cells, Cultured
- Disease Models, Animal
- Drug Administration Routes
- Fluorescent Dyes
- Hyperplasia
(chemically induced, metabolism, pathology)
- Immunoblotting
- Inflammation
(chemically induced, pathology)
- Macrophages
(pathology)
- Muscle, Smooth, Vascular
(cytology, drug effects, metabolism)
- Osteopontin
- RNA
(metabolism)
- Rabbits
- Receptors, Purinergic P2
(genetics, metabolism)
- Receptors, Purinergic P2Y2
- Sialoglycoproteins
(biosynthesis)
- Tunica Intima
(drug effects, metabolism, pathology)
- Up-Regulation
- Uridine Triphosphate
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