| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1Department of Medicine, Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21224; and 2Department of Obstetrics and Gynecology, Indiana University School of Medicine, Indianapolis, Indiana 46202
Submitted 27 November 2002 ; accepted in final form 18 July 2003
Diperoxovanadate (DPV), a potent inhibitor of protein tyrosine phosphatases and activator of tyrosine kinases, alters endothelial barrier function via signaling pathways that are incompletely understood. One potential pathway is Src kinase-mediated tyrosine phosphorylation of proteins such as cortactin that regulate endothelial cell (EC) cytoskeleton assembly. As DPV modulates endothelial cell signaling via protein tyrosine phosphorylation, we determined the role of DPV-induced intracellular free calcium concentration ([Ca2+]i) in activation of Src kinase, cytoskeletal remodeling, and barrier function in bovine pulmonary artery endothelial cells (BPAECs). DPV in a dose- and time-dependent fashion increased [Ca2+]i, which was partially blocked by the calcium channel blockers nifedipine and Gd3+. Treatment of cells with thapsigargin released Ca2+ from the endoplasmic reticulum, and subsequent addition of DPV caused no further change in [Ca2+]i. These data suggest that DPV-induced [Ca2+]i includes Ca release from the endoplasmic reticulum and Ca influx through store-operated calcium entry. Furthermore, DPV induced an increase in protein tyrosine phosphorylation, phosphorylation of Src and cortactin, actin remodeling, and altered transendothelial electrical resistance in BPAECs. These DPV-mediated effects were significantly attenuated by BAPTA (25 µM), a chelator of [Ca2+]i. Immunofluorescence studies reveal that the DPV-mediated colocalization of cortactin with peripheral actin was also prevented by BAPTA. Chelation of extracellular Ca2+ by EGTA had marginal effects on DPV-induced phosphorylation of Src and cortactin; actin stress fibers formation, however, affected EC barrier function. These data suggest that DPV-induced changes in [Ca2+]i regulate endothelial barrier function using signaling pathways that involve Src and cytoskeleton remodeling.
intracellular calcium; endothelial cells; Src kinase; cytoskeleton; cortactin
This article has been cited by other articles:
|
|
 |
|
  K. Hamanaka, M.-Y. Jian, D. S. Weber, D. F. Alvarez, M. I. Townsley, A. B. Al-Mehdi, J. A. King, W. Liedtke, and J. C. Parker TRPV4 initiates the acute calcium-dependent permeability increase during ventilator-induced lung injury in isolated mouse lungs Am J Physiol Lung Cell Mol Physiol, October 1, 2007; 293(4): L923 - L932. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Mirzapoiazova, I. Kolosova, P. V. Usatyuk, V. Natarajan, and A. D. Verin Diverse effects of vascular endothelial growth factor on human pulmonary endothelial barrier and migration Am J Physiol Lung Cell Mol Physiol, October 1, 2006; 291(4): L718 - L724. [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]
|
|
|
|
|
|
P. V. Usatyuk and V. Natarajan Regulation of reactive oxygen species-induced endothelial cell-cell and cell-matrix contacts by focal adhesion kinase and adherens junction proteins Am J Physiol Lung Cell Mol Physiol, December 1, 2005; 289(6): L999 - L1010. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
