|
|
||||||||
Departments of 1 Pathology and 2 Medicine, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2650
We examined the hypothesis that the
potent vasoconstrictor endothelin (ET)-1 regulates both its own
production and production of the vasodilator prostaglandins
PGE2 and prostacyclin in sheep peripheral lung vascular
smooth muscle cells (PLVSMC). Confluent layers of PLVSMC were exposed
to 10 nM ET-1; expression of the prepro (pp)-ET-1, cyclooxygenase
(COX)-1, and COX-2 genes was examined by RT-PCR and Western
analysis. Intracellular levels of ET-1 were measured by ELISA
with and without addition of the protein synthesis inhibitor brefeldin
A (50 µg/ml). Prostaglandin levels were measured by gas
chromatography-mass spectrometry. Through use of ETA and
ETB antagonists (BQ-610 and BQ-788, respectively), the
contribution of the ET receptors to COX-1 and -2 expression and ppET-1
gene expression was examined. The contribution of phosphorylated p38
and p44/42 MAPK on COX-1 and COX-2 expression was also examined with
MAPK inhibitors (p38, SB-203580 and p44/42, PD-98056). ET-1 resulted in
transient increases in ppET-1, COX-1, and COX-2 gene and protein
expression and release of 6-keto-PGF1
and
PGE2 (P < 0.05). Both internalization of
ET-1 and synthesis of new peptide contributed to an increase in
intracellular ET-1 (P < 0.05). Although increased
ppET-1 was regulated by both ETA and ETB, COX-2
expression was upregulated only by ETA; COX-1 expression was unaffected by either antagonist. ET-1 treatment resulted in transient phosphorylation of p38 and p44/42 MAPK; inhibitors of these
MAPKs suppressed expression of COX-2 but not COX-1. Our data indicate
that local production of ET-1 regulates COX-2 by activation of the
ETA receptor and phosphorylation of p38 and p44/42 MAPK in PLVSMC.
prostacyclin; prostaglandin E2; endothelin receptors
This article has been cited by other articles:
![]() |
U. Hink and T. Munzel COX-2, Another Important Player in the Nitric Oxide-Endothelin Cross-Talk: Good News for COX-2 Inhibitors? Circ. Res., June 9, 2006; 98(11): 1344 - 1346. [Full Text] [PDF] |
||||
![]() |
Y. Zhou, S. Mitra, S. Varadharaj, N. Parinandi, J. L. Zweier, and N. A. Flavahan Increased Expression of Cyclooxygenase-2 Mediates Enhanced Contraction to Endothelin ETA Receptor Stimulation in Endothelial Nitric Oxide Synthase Knockout Mice Circ. Res., June 9, 2006; 98(11): 1439 - 1445. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Migneault, S. Sauvageau, L. Villeneuve, E. Thorin, A. Fournier, N. Leblanc, and J. Dupuis Chronically Elevated Endothelin Levels Reduce Pulmonary Vascular Reactivity to Nitric Oxide Am. J. Respir. Crit. Care Med., March 1, 2005; 171(5): 506 - 513. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Spinella, L. Rosano, V. Di Castro, M. R. Nicotra, P. G. Natali, and A. Bagnato Inhibition of Cyclooxygenase-1 and -2 Expression by Targeting the Endothelin A Receptor in Human Ovarian Carcinoma Cells Clin. Cancer Res., July 15, 2004; 10(14): 4670 - 4679. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |