Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1993-4-6
pubmed:abstractText
Plasminogen activator inhibitor type 1 (PAI-1), the physiologic inhibitor of both tissue-type plasminogen activator (tPA) and urokinase-type plasminogen activator (uPA), is a major biosynthetic product of endothelial cells in vitro; endothelial cells in vivo, in contrast, do not appear to produce significant amounts of PAI-1 as made evident by in situ-hybridization studies in normal mice. This suggests that the high rate of PAI-1 synthesis of endothelial cells in vitro might be a result of the culture conditions. When human umbilical vein endothelial cells (HUVEC) were grown on human amniotic membranes, resembling the natural growth support instead of coated plastic, their morphology was changed from the cobblestone-like appearance on plastic to an in vivo like flagstone pattern. However, this morphological change had no significant effect on the synthesis and secretion of PAI-1. When smooth muscle cell (SMC) conditioned media (CM) were added to HUVEC cultures, PAI-1 antigen secretion of HUVEC was reduced by 40% to 60% as measured by enzyme-linked immunosorbent assay (ELISA). Immunoprecipitation experiments using 36S-methionine metabolically labeled HUVEC and Northern blot analysis of HUVEC PAI-1 mRNA indicate that this reduction was attributable to decreased PAI-1 synthesis and reduced steady-state levels of both the 3.2 kb and 2.2 kb form of PAI-1 mRNA. This effect was dose-dependent and observed under serum-containing as well as serum-free conditions, in the absence or presence of endothelial cell growth supplement (ECGS, 0 to 100 micrograms/mL) and attributable to a nondialyzable factor. Our data suggest that the high level of PAI-1 biosynthesis of endothelial cells in vitro may be attributable to the lack of a soluble factor produced by SMC, which controls and suppresses PAI-1 biosynthesis of endothelial cells in vivo.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
81
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1277-83
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Type 1 plasminogen activator inhibitor synthesis of endothelial cells is downregulated by smooth muscle cells.
pubmed:affiliation
Laboratory for Clinical Experimental Physiology, University of Vienna, Austria.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't