Endothelial contraction and monolayer hyperpermeability are regulated by Src kinase

Endothelial monolayer hyperpermeability is regulated by a myosin light chain phosphorylation (MLCP)-dependent contractile mechanism. In this study, we tested the role of Src-dependent tyrosine phosphorylation to modulate endothelial contraction and monolayer barrier function with the use of the myos...

Full description

Saved in:
Bibliographic Details
Published in:American journal of physiology. Heart and circulatory physiology 2003-03, Vol.53 (3), p.H994-H1002
Main Authors: MUCHA, David R, MYERS, Carter L, SCHAEFFER, Richard C
Format: Article
Language:English
Subjects:
Air breathing
Biological and medical sciences
Digital imaging
Fluorescence
Fundamental and applied biological sciences. Psychology
Heart
Respiratory system: anatomy, metabolism, gas exchange, ventilatory mechanics, respiratory hemodynamics
Vertebrates: respiratory system
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Endothelial monolayer hyperpermeability is regulated by a myosin light chain phosphorylation (MLCP)-dependent contractile mechanism. In this study, we tested the role of Src-dependent tyrosine phosphorylation to modulate endothelial contraction and monolayer barrier function with the use of the myosin phosphatase inhibitor calyculin A (CalA) to directly elevate MLCP with the Src family tyrosine kinase inhibitor herbimycin A (HA) in bovine pulmonary artery endothelial cells (EC). CalA stimulated an increase in MLCP, Src kinase activity, an increase in the tyrosine phosphorylation of paxillin and focal adhesion (FA) kinase (p125FAK), and monolayer hyperpermeability. Microscopic examination of CalA-treated EC revealed a contractile morphology characterized by peripheral contractile bands of actomyosin filaments and stress fibers linked to phosphotyrosine-containing FAs. These CalA-dependent events were HA sensitive. HA alone stimulated an improvement in monolayer barrier formation by reducing the levels of MLCP and phosphotyrosine-containing proteins and the number of large paracellular holes. These data show that Src kinase plays an important role in regulating monolayer hyperpermeability through adjustments in tyrosine phosphorylation, MLCP, and EC contraction. [PUBLICATION ABSTRACT]
ISSN:0363-6135
1522-1539