test Browse by Author Names Browse by Titles of Works Browse by Subjects of Works Browse by Issue Dates of Works

Advanced Search
& Collections
Issue Date   
Sign on to:   
Receive email
My Account
authorized users
Edit Profile   
About T-Space   

T-Space at The University of Toronto Libraries >
Faculty of Medicine >
Faculty Publications >

Please use this identifier to cite or link to this item: http://hdl.handle.net/1807/17896

Title: Vitronectin stabilizes thrombi and vessel occlusion but plays a dual role in platelet aggregation
Authors: Reheman, A
Gross, P
Yang, H
Chen, P
Allen, D
Leytin, V
Freedman, J
Ni, H
Department: Laboratory Medicine and Pathobiology
St. Michael's Hospital
Keywords: intravital microscopy
platelet aggregation
Issue Date: 1-May-2005
Publisher: Blackwell Publishing
Citation: Reheman A et al. Vitronectin stabilizes thrombi and vessel occlusion but plays a dual role in platelet aggregation. J Thromb Haemost. 2005;3(5):875-83.
Abstract: The role of vitronectin (Vn) in thrombosis is currently controversial; both inhibitory and supportive roles have been reported. To monitor directly the function of Vn in thrombotic events at the site of vascular injury, we studied Vn-deficient (Vn-/-) and wild-type (WT) control mice with two real-time intravital microscopy thrombosis models. In the mesenteric arteriole model, vessel injury was induced by ferric chloride. We observed unstable thrombi and a significantly greater number of emboli in Vn-/- mice. Vessel occlusion was also delayed and frequent vessel re-opening occurred. In the cremaster muscle arteriole model, vessel injury was induced by a nitrogen dye laser. We observed significantly fewer platelets, lower fibrin content, and unstable fibrin within the thrombi of Vn-/- mice. To define further the role of Vn in thrombus growth, we studied platelet aggregation in vitro. Consistent with our in vivo data, the second wave of thrombin-induced aggregation of gel-filtered platelets was abolished at a low concentration of thrombin in Vn-/- platelets. Interestingly, adenosine diphosphate (ADP)-induced platelet aggregation was significantly increased in Vn-/- platelet-rich plasma (PRP) and this effect was attenuated by adding purified plasma Vn. We also observed increased platelet aggregation induced by shear stress in Vn-/- whole blood. These data demonstrate that Vn is a thrombus stabilizer. However, in contrast to released platelet granule Vn which enhances platelet aggregation, plasma Vn inhibits platelet aggregation.
URI: http://hdl.handle.net/1807/17896
ISSN: 1538-7933
Appears in Collections:Faculty Publications

Files in This Item:

File Description SizeFormat
Vitronectin stabilizes thrombi and vessel occlusion but plays a dual role in platelet aggregation.pdf370.84 kBAdobe PDF

Items in T-Space are protected by copyright, with all rights reserved, unless otherwise indicated.