Thrombosis |
From the Vascular Biology Laboratory, Weston Centre for Experimental Research, Thrombosis Research Institute, London, and the Department of Histopathology (T.K.), Imperial College School of Medicine, Hammersmith Hospital, London, UK.
Correspondence to Dr Florea Lupu, Vascular Biology Laboratory, Thrombosis Research Institute, Emmanuel Kaye Building, Manresa Road, Chelsea, London SW3 6LR, UK. E-mail flupu{at}tri-london.ac.uk
AbstractFluid flow modulates the synthesis and secretion by endothelial cells (ECs) of several proteins that control the hemostatic properties of the vessel wall. Tissue factor pathway inhibitor (TFPI), also synthesized by ECs, is the main downregulator of tissue factordependent procoagulant activity. In the present study, we investigated the effect of physiological shear stress on the expression, distribution, and release of TFPI in cultured ECs. The EA.hy926 cell line was grown in a hollow-fiber perfusion system and exposed for variable times to different shear values: 0.27 dyne/cm2 (minimal flow), 4.1 dyne/cm2 (venous flow), and 19 dyne/cm2 (moderate arterial flow). Step increase of the shear stress from 0.27 to 19 dyne/cm2 induced a sharp increase of TFPI released into the medium and a parallel decrease and redistribution of cell-associated TFPI, which suggests that an acute release of TFPI occurred from the cellular pools. During 24 hours of high shear stress, cell-associated TFPI antigen and mRNA increased time-dependently. Subjecting ECs to steady shear stress for 72 hours also upregulated the expression and production of TFPI, in direct correlation with the degree of the shear. The secretion of TFPI was enhanced 1.9-fold under venous flow and 2.4-fold under arterial flow compared with minimal flow. Equally, cell-associated TFPI antigen and cell surface TFPI activity increased proportionally with the shear stress. The expression of TFPI mRNA, as determined by Northern blotting, increased up to 2-fold in ECs under venous flow and up to 3-fold under arterial flow. These results suggest that shear forces regulate TFPI by modulating its release and gene expression in ECs in vitro.
Key Words: tissue factor pathway inhibitor shear stress flow endothelial cells
This article has been cited by other articles:
![]() |
J. T.B. Crawley and D. A. Lane The Haemostatic Role of Tissue Factor Pathway Inhibitor Arterioscler Thromb Vasc Biol, February 1, 2008; 28(2): 233 - 242. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Lupu, A. D. Westmuckett, G. Peer, L. Ivanciu, H. Zhu, F. B. Taylor Jr., and F. Lupu Tissue Factor-Dependent Coagulation Is Preferentially Up-Regulated within Arterial Branching Areas in a Baboon Model of Escherichia coli Sepsis Am. J. Pathol., October 1, 2005; 167(4): 1161 - 1172. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Lupu, X. Hu, and F. Lupu Caveolin-1 Enhances Tissue Factor Pathway Inhibitor Exposure and Function on the Cell Surface J. Biol. Chem., June 10, 2005; 280(23): 22308 - 22317. [Abstract] [Full Text] [PDF] |
||||
|
ATVB Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2000 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |