Linked Life Data

8798766

Source:http://linkedlifedata.com/resource/pubmed/id/8798766

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
40
pubmed:dateCreated
1996-11-25
pubmed:abstractText
Low density lipoprotein receptor-related protein (LRP) is a multifunctional receptor, expressed by vascular smooth muscle cells (VSMCs) in normal arteries and in atherosclerotic lesions. In this investigation, we demonstrate a novel mechanism for the regulation of LRP activity in cultured rat aortic VSMCs. Cells that were treated with platelet-derived growth factor-BB (PDGF-BB) or epidermal growth factor (EGF) for 24 h bound increased amounts of the LRP ligand, activated alpha2-macroglobulin (alpha2M), at 4 degrees C. The Bmax for activated alpha2M was increased from 56 +/- 5 to 178 +/- 24 and 143 +/- 11 fmol/mg cell protein by PDGF-BB and EGF, respectively, while the KD was unchanged. Northern and Western blot analyses demonstrated that neither PDGF-BB nor EGF increase LRP mRNA or protein levels. Instead, LRP was redistributed to the cell surface and remained localized primarily in coated pits, as determined by surface protein biotinylation, affinity labeling, and immunoelectron microscopy studies. The increase in cell-surface LRP was partially explained by a 50% decrease in receptor endocytosis rate; however, at 37 degrees C, PDGF-BB- and EGF-treated VSMCs still bound/internalized increased amounts of activated alpha2M and subsequently released increased amounts of trichloroacetic acid-soluble radioactivity. The cytokine-induced shifts in LRP subcellular distribution were stable when VSMCs were challenged with a saturating concentration of ligand and then incubated, in the absence of cytokine, for 2.5 h at 37 degrees C. Regulation of LRP distribution and activity may be an important aspect of the VSMC response to the atherogenic cytokines, PDGF-BB and EGF.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
4
pubmed:volume
271
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
24894-900
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Epidermal growth factor and platelet-derived growth factor-BB induce a stable increase in the activity of low density lipoprotein receptor-related protein in vascular smooth muscle cells by altering receptor distribution and recycling.
pubmed:affiliation
Department of Biochemistry, University of Virginia Health Sciences Center, Charlottesville, Virginia 22908, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.