|
|
||||||||
Institute For Environmental Medicine, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104
Ischemia in the intact ventilated lung (oxygenated ischemia) leads to endothelial generation of reactive oxygen species (ROS) and nitric oxide (NO). This study investigated the signaling pathway for NO generation with oxygenated ischemia in bovine pulmonary artery endothelial cells (BPAEC) that were flow adapted in vitro. BPAECs were cultured in an artificial capillary system and subjected to abrupt cessation of flow (ischemia) under conditions where cellular oxygenation was maintained. Immunoblotting and dichlorofluorescein/triazolofluorescein fluorescence were used to assess extracellular signal-regulated kinases 1 and 2 (ERK1/2) phosphorylation and ROS/NO generation, respectively. ERK1/2 phosphorylation significantly increased during ischemia, whereas total ERK1/2 did not change. ERK1/2 phosphorylation was suppressed by an inhibitor of tyrosine phosphorylation (genestein), cholesterol-binding reagents (filipin or cyclodextrin), or inhibitors of ROS (diphenyleneiodonium, N-acetylcysteine, or catalase), suggesting a role for both membrane cholesterol and ROS in ERK1/2 activation. Ischemia resulted in a 1.8-fold increase in NO generation that was suppressed by inhibitors of ERK1/2 activation (PD-98059 or U-0126). A calmodulin inhibitor (calmidizolium) or removal of Ca2+ from the medium also blocked NO generation, indicating that endothelial NO synthase (eNOS) is the activated isoform. These results indicate ischemia induces NO generation (possibly through a membrane cholesterol-sensitive flow sensor), the ERK1/2 cascade mediates signaling from the sensor to eNOS, and ROS are required for ERK activation.
shear stress; reactive oxygen species; membrane cholesterol
This article has been cited by other articles:
![]() |
W. Kwok, S. H. Lee, C. Culberson, K. Korneszczuk, and M. G. Clemens Caveolin-1 mediates endotoxin inhibition of endothelin-1-induced endothelial nitric oxide synthase activity in liver sinusoidal endothelial cells Am J Physiol Gastrointest Liver Physiol, November 1, 2009; 297(5): G930 - G939. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. J. Bernal, K. Leelavanichkul, E. Bauer, R. Cao, A. Wilson, K. J. Wasserloos, S. C. Watkins, B. R. Pitt, and C. M. St. Croix Nitric Oxide-Mediated Zinc Release Contributes to Hypoxic Regulation of Pulmonary Vascular Tone Circ. Res., June 20, 2008; 102(12): 1575 - 1583. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Milovanova, S. Chatterjee, Y. Manevich, I. Kotelnikova, K. DeBolt, M. Madesh, J. S. Moore, and A. B. Fisher Lung endothelial cell proliferation with decreased shear stress is mediated by reactive oxygen species Am J Physiol Cell Physiol, January 1, 2006; 290(1): C66 - C76. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Chatterjee, A.-B. Al-Mehdi, I. Levitan, T. Stevens, and A. B. Fisher Shear stress increases expression of a KATP channel in rat and bovine pulmonary vascular endothelial cells Am J Physiol Cell Physiol, October 1, 2003; 285(4): C959 - C967. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. P. Nase, J. Tuttle, and H. G. Bohlen Reduced perivascular PO2 increases nitric oxide release from endothelial cells Am J Physiol Heart Circ Physiol, July 11, 2003; 285(2): H507 - H515. [Abstract] [Full Text] [PDF] |
||||
![]() |
W.-I. Choi, D. A. Quinn, K. M. Park, R. K. Moufarrej, B. Jafari, O. Syrkina, J. V. Bonventre, and C. A. Hales Systemic Microvascular Leak in an In Vivo Rat Model of Ventilator-induced Lung Injury Am. J. Respir. Crit. Care Med., June 15, 2003; 167(12): 1627 - 1632. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |