Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2003-9-12
pubmed:abstractText
The atherogenic serum lysophosphatidylcholine (LPC) is known to mediate vascular endothelial responses ranging from upregulation of adhesion molecules and growth factors to secretion of chemokines and superoxide anion. We investigated whether endothelial cells express receptors for LPC, which may account for their actions. Human brain microvascular (HBMEC) and dermal microvascular endothelial cells (HMEC) were prepared for RT-PCR analysis for possible expression of the G protein-coupled receptors, GPR4 and G2A, which are believed to be specific LPC receptors. Results indicated that HBMEC expressed low basal GPR4 mRNA, but stimulation with tumor necrosis factor-alpha (TNF-alpha) (100 U/ml) or H2O2 (50 micromol/l) for 2 h or overnight upregulated expression severalfold. In contrast, HMEC expressed high basal GPR4 mRNA, which was not further increased by either TNF-alpha or H2O2 stimulation. Another LPC receptor, G2A, was not detected in either endothelial cell type. Competition binding studies were made to evaluate specific binding of [3H]LPC to the intact endothelial cell monolayer. Basal specific [3H]LPC binding in HBMEC was approximately eight times lower than in HMEC; however, TNF-alpha or H2O2 stimulation increased [3H]LPC binding on HMBEC but not HMEC. The results indicated that GPR4 expression was consistent with specific [3H]LPC binding. Overall, we report that endothelial cells selectively expressed GPR4, a specific LPC receptor. Furthermore, GPR4 expression by HBMEC, but not HMEC, was increased by inflammatory stresses. We conclude that endogenous GPR4 in endothelial cells may be a potential G protein-coupled receptor by which LPC signals proinflammatory activities.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0363-6135
pubmed:author
pubmed:issnType
Print
pubmed:volume
285
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1786-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Inflammatory stress increases receptor for lysophosphatidylcholine in human microvascular endothelial cells.
pubmed:affiliation
Department of Pharmacology, Rush-Presbyterian St. Luke's Medical Center, 2242 W. Harrison St., Suite 260, Chicago, IL 60612, USA. hlum@rush.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't