Linked Life Data

2040630

Source:http://linkedlifedata.com/resource/pubmed/id/2040630

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
17
pubmed:dateCreated
1991-7-10
pubmed:abstractText
We demonstrate that unstimulated platelets attach to immobilized fibrinogen in a selective process mediated by the membrane glycoprotein (GP) complex IIb-IIIa (alpha IIb beta 3). The initial attachment, independent of platelet activation, is followed by spreading and irreversible adhesion even in the presence of activation inhibitors. Using fibrinogen fragments derived from plasmin digestion, we found that unstimulated platelets do not attach to immobilized fragment E, which contains an Arg-Gly-Asp sequence at A alpha 95-97, and adhere to fragments X and D, both containing the gamma 400-411 dodecapeptide adhesion sequence, less efficiently than to intact fibrinogen. Thus, the carboxyl terminus of the A alpha chain, missing in the "early" fragment X used in these studies, appears to be involved in the interaction of fibrinogen with unstimulated platelets. In contrast, activated platelets adhere to immobilized fibrinogen and fragments X, D, and E in a time-dependent and equivalent manner. Although activated platelets adhere to immobilized vitronectin, fibronectin, and von Willebrand factor through GP IIb-IIIa, unstimulated platelets fail to adhere to vitronectin and have only a limited capacity to adhere to fibronectin and von Willebrand factor. These results demonstrate that GP IIb-IIIa on unstimulated platelets displays a recognition specificity for attachment to immobilized adhesive proteins that is distinct from that seen following platelet activation. Thus, unstimulated platelets selectively interact with fibrinogen, and the initial attachment is followed by spreading and irreversible adhesion in the absence of exogenous agonists. This process may be regulated by plasmin cleavage of the fibrinogen A alpha chain and may play an important role during normal hemostasis and during the pathological development of thrombotic vascular occlusions.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
266
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11227-33
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Selective recognition of adhesive sites in surface-bound fibrinogen by glycoprotein IIb-IIIa on nonactivated platelets.
pubmed:affiliation
Roon Research Center for Arteriosclerosis and Thrombosis, Department of Molecular and Experimental Medicine, Research Institute of Scripps Clinic, La Jolla, California 92037.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't