Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
17
pubmed:dateCreated
1990-7-16
pubmed:abstractText
Urokinase-type plasminogen activator (uPA) binds to a specific receptor on various cell types, the bound molecule retaining its enzymatic activity against plasminogen. We have now investigated whether receptor-bound uPA also retains the ability to react with and be inhibited by plasminogen activator inhibitors (PAI-1 and PAI-2). uPA bound to its receptor on human U937 monocyte-like cells was inhibited by PAI-1 (in its active form in the presence of vitronectin fragments) with an association rate constant of 4.5 x 10(6) M-1 s-1, which was 40% lower than that obtained for uPA in solution (7.9 x 10(6) M-1 s-1). The inhibition of uPA by PAI-2 was decreased to a similar extent by receptor binding, falling from 5.3 x 10(5) to 3.3 x 10(5) M-1 s-1. Stimulation of U937 cells with phorbol 12-myristate 13-acetate was accompanied by a further reduction in receptor-bound uPA inhibition by PAI-1 and PAI-2 to 1.7 x 10(6) and 1.1 x 10(5) M-1 s-1, respectively. These constants although lower than those for uPA in solution still represent rather rapid inhibition of the enzyme, and demonstrate that uPA bound to its specific cellular receptor remains available for efficient inhibition by PAI's, which may therefore play a major role in controlling cell-surface plasminogen activation and extracellular proteolytic activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Antibodies, http://linkedlifedata.com/resource/pubmed/chemical/Antigen-Antibody Complex, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Precursors, http://linkedlifedata.com/resource/pubmed/chemical/PLAUR protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Plasminogen, http://linkedlifedata.com/resource/pubmed/chemical/Plasminogen Activators, http://linkedlifedata.com/resource/pubmed/chemical/Plasminogen Inactivators, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Cell Surface, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Urokinase Plasminogen..., http://linkedlifedata.com/resource/pubmed/chemical/Tetradecanoylphorbol Acetate, http://linkedlifedata.com/resource/pubmed/chemical/Urokinase-Type Plasminogen Activator
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9904-8
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Inhibition of receptor-bound urokinase by plasminogen-activator inhibitors.
pubmed:affiliation
Finsen Laboratory, Rigshospitalet, Copenhagen, Denmark.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't