Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
8
|
pubmed:dateCreated |
1991-5-21
|
pubmed:abstractText |
In this study, the question of whether glycoprotein Ib (GPIb) mediates both high and moderate affinity pathways of alpha-thrombin-induced platelet activation was examined. Flow cytometric studies, using a panel of monoclonal antibodies (MoAbs), showed that Serratia marcescens protease treatment removed greater than 97% of the glycocalicin portion of GPIb but did not affect the changes in the expression of GPIX or GMP-140 that were induced by high concentrations of alpha-thrombin (10 nmol/L). However, Serratia treatment almost completely abolished the increase in platelet surface GMP-140 induced by low concentrations of alpha-thrombin (0.5 nmol/L) and diminished the downregulation of platelet surface GPIX by 60.9% +/- 5.6% (mean +/- SEM, n = 3). When present in 20-fold molar excess, an MoAb directed against the alpha-thrombin/von Willebrand factor (vWf) binding domains of GPIb completely blocked the ristocetin-dependent binding of vWf to platelets but inhibited only to about 50% the binding of alpha-thrombin and the activation-dependent binding of vWf. In platelets treated with Serratia marcescens protease to remove GPIb, a concentration of this MoAb 16,000-fold in excess of the maximum possible remaining copies of GPIb failed to inhibit platelet activation by alpha-thrombin. These studies demonstrate that activation of intact platelets by alpha-thrombin proceeds by both GPIb-dependent and GPIb-independent mechanisms.
|
pubmed:grant | |
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
AIM
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Antibodies, Monoclonal,
http://linkedlifedata.com/resource/pubmed/chemical/Endopeptidases,
http://linkedlifedata.com/resource/pubmed/chemical/Platelet Membrane Glycoproteins,
http://linkedlifedata.com/resource/pubmed/chemical/Thrombin,
http://linkedlifedata.com/resource/pubmed/chemical/von Willebrand Factor
|
pubmed:status |
MEDLINE
|
pubmed:month |
Apr
|
pubmed:issn |
0006-4971
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:day |
15
|
pubmed:volume |
77
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
1740-8
|
pubmed:dateRevised |
2007-11-14
|
pubmed:meshHeading |
pubmed-meshheading:2015400-Antibodies, Monoclonal,
pubmed-meshheading:2015400-Binding Sites,
pubmed-meshheading:2015400-Blood Platelets,
pubmed-meshheading:2015400-Endopeptidases,
pubmed-meshheading:2015400-Humans,
pubmed-meshheading:2015400-Kinetics,
pubmed-meshheading:2015400-Platelet Activation,
pubmed-meshheading:2015400-Platelet Membrane Glycoproteins,
pubmed-meshheading:2015400-Serratia marcescens,
pubmed-meshheading:2015400-Thrombin,
pubmed-meshheading:2015400-von Willebrand Factor
|
pubmed:year |
1991
|
pubmed:articleTitle |
Glycoprotein Ib (GPIb)-dependent and GPIb-independent pathways of thrombin-induced platelet activation.
|
pubmed:affiliation |
Department of Cardiovascular Research, Tokyo Metropolitan Institute of Medical Science, Japan.
|
pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, U.S. Gov't, P.H.S.
|