|
|
||||||||
1Institute of Anatomy and Cell Biology, University of Würzburg, D-97070 Würzburg; 2Department of Pharmacology and Toxicology, Albert-Ludwigs-University, D-79104 Freiburg, Germany; and 3Department of Human Physiology, University of California, Davis, California 95616
Submitted 13 March 2003 ; accepted in final form 18 September 2003
Our previous experiments indicated that GTPases, other than RhoA, are important for the maintenance of endothelial barrier integrity in both intact microvessels of rats and mice and cultured mouse myocardial endothelial (MyEnd) cell monolayers (J Physiol 539: 295308, 2002). In the present study, we inhibited the endothelial GTPase Rac by Clostridium sordellii lethal toxin (LT) and investigated the relation between the degree of inhibition of Rac by glucosylation and increased endothelial barrier permeability. In rat venular microvessels, LT (200 ng/ml) increased hydraulic conductivity from a control value of 2.5 ± 0.6 to 100.8 ± 18.7 x 107 cm·s1·cmH2O1 after 80 min. In cultured MyEnd cells exposed to LT (200 ng/ml), up to 60% of cellular Rac was glucosylated after 90 min, resulting in depolymerization of F-actin and interruptions of junctional distribution of vascular endothelial cadherin (VE-cadherin) and
-catenin as well as the formation of intercellular gaps. To understand the mechanism by which inhibition of Rac caused disassembly of adherens junctions, we used laser tweezers to quantify VE-cadherin-mediated adhesion. LT and cytochalasin D, an actin depolymerizing agent, both reduced adhesion of VE-cadherin-coated microbeads to the endothelial cell surface, whereas the inhibitor of Rho kinase Y-27632 did not. Stabilization of actin filaments by jasplakinolide completely blocked the effect of cytochalasin D but not of LT on bead adhesion. We conclude that Rac regulates endothelial barrier properties in vivo and in vitro by 1) modulation of actin filament polymerization and 2) acting directly on the tether between VE-cadherin and the cytoskeleton.
vascular endothelial cadherin; adherens junction; permeability; Rho proteins; actin
This article has been cited by other articles:
![]() |
V. Solodushko, J. C. Parker, and B. Fouty Pulmonary Microvascular Endothelial Cells Form a Tighter Monolayer when Grown in Chronic Hypoxia Am. J. Respir. Cell Mol. Biol., April 1, 2008; 38(4): 491 - 497. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Muller-Marschhausen, J. Waschke, and D. Drenckhahn Physiological hydrostatic pressure protects endothelial monolayer integrity Am J Physiol Cell Physiol, January 1, 2008; 294(1): C324 - C332. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Schlegel, S. Burger, N. Golenhofen, U. Walter, D. Drenckhahn, and J. Waschke The role of VASP in regulation of cAMP- and Rac 1-mediated endothelial barrier stabilization Am J Physiol Cell Physiol, January 1, 2008; 294(1): C178 - C188. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. R. Jacobson, S. M. Dudek, P. A. Singleton, I. A. Kolosova, A. D. Verin, and J. G. N. Garcia Endothelial cell barrier enhancement by ATP is mediated by the small GTPase Rac and cortactin. Am J Physiol Lung Cell Mol Physiol, August 1, 2006; 291(2): L289 - L295. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Mehta and A. B. Malik Signaling Mechanisms Regulating Endothelial Permeability Physiol Rev, January 1, 2006; 86(1): 279 - 367. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. H. Adamson and F. E. Curry Ang-1: Tie-ing up endothelial adhesion? Am J Physiol Heart Circ Physiol, January 1, 2006; 290(1): H74 - H76. [Full Text] [PDF] |
||||
![]() |
F. Baffert, T. Le, G. Thurston, and D. M. McDonald Angiopoietin-1 decreases plasma leakage by reducing number and size of endothelial gaps in venules Am J Physiol Heart Circ Physiol, January 1, 2006; 290(1): H107 - H118. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. H. Adamson, J. C. Ly, M. Fernandez-Miyakawa, S. Ochi, J. Sakurai, F. Uzal, and F. E. Curry Clostridium perfringens Epsilon-Toxin Increases Permeability of Single Perfused Microvessels of Rat Mesentery Infect. Immun., August 1, 2005; 73(8): 4879 - 4887. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Wojciak-Stothard, L. Y. F. Tsang, and S. G. Haworth Rac and Rho play opposing roles in the regulation of hypoxia/reoxygenation-induced permeability changes in pulmonary artery endothelial cells Am J Physiol Lung Cell Mol Physiol, April 1, 2005; 288(4): L749 - L760. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Waschke, F. E. Curry, R. H. Adamson, and D. Drenckhahn Regulation of actin dynamics is critical for endothelial barrier functions Am J Physiol Heart Circ Physiol, March 1, 2005; 288(3): H1296 - H1305. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Liu, D. C. Cara, J. Kaur, E. Raharjo, S. C. Mullaly, J. Jongstra-Bilen, J. Jongstra, and P. Kubes LSP1 is an endothelial gatekeeper of leukocyte transendothelial migration J. Exp. Med., February 7, 2005; 201(3): 409 - 418. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Waschke, D. Drenckhahn, R. H. Adamson, H. Barth, and F. E. Curry cAMP protects endothelial barrier functions by preventing Rac-1 inhibition Am J Physiol Heart Circ Physiol, December 1, 2004; 287(6): H2427 - H2433. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Waschke, D. Drenckhahn, R. H. Adamson, and F. E. Curry Role of adhesion and contraction in Rac 1-regulated endothelial barrier function in vivo and in vitro Am J Physiol Heart Circ Physiol, August 1, 2004; 287(2): H704 - H711. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |