Linked Life Data

8463253

Source:http://linkedlifedata.com/resource/pubmed/id/8463253

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1993-5-5
pubmed:abstractText
Activation of human platelets by complement proteins, C5b-9, thrombin plus collagen, or a Ca2+ ionophore results in surface exposure of phosphatidylserine (PS), accompanied by the expression of membrane catalytic activity for the tenase (VIIaIXa) and prothrombinase (VaXa) coagulation enzyme complexes. The mechanism underlying this surface exposure of PS upon platelet activation remains unresolved. Using fluorescent derivatives of PS (NBD-PS), we have investigated how the transmembrane migration of PS is related to microvesiculation of the platelet plasma membrane and to fusion of storage granules with the plasma membrane. Gel-filtered platelets were incubated with NBD-PS, allowing 90 +/- 10% of the incorporated NBD-PS to accumulate into the inner leaflet of the plasma membrane. Migration of NBD-PS from the inner leaflet to the plasma membrane surface was monitored by time-based flow cytometry, and correlated with the appearance of platelet microparticles and alpha-granule secretion. Platelet activation by C5b-9 or the Ca2+ ionophore, A23187, increased surface exposure of NBD-PS, due to acceleration of the apparent rate of migration from inner to outer plasma membrane leaflets. The onset of this accelerated migration of NBD-PS to the surface coincided with the onset of plasma membrane vesiculation, and the NBD-PS that partitioned into the membrane of the shed microparticle was also rapidly exposed to the surface (t1/2 < 2 min). In addition to a temporal correlation, microparticle formation and the surface exposure of inner leaflet NBD-PS showed a similar requirement for Ca2+. These results demonstrate that agonist-induced microvesiculation of the platelet plasma membrane is accompanied by accelerated migration of a PS analogue from the inner leaflet to the surface of the shed microparticle membrane, suggesting the mechanism by which induction of platelet microparticle formation exposes catalytic surface for tenase and prothrombinase assembly.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
268
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7171-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:8463253-Alkaloids, pubmed-meshheading:8463253-Biological Transport, pubmed-meshheading:8463253-Blood Platelets, pubmed-meshheading:8463253-Calcimycin, pubmed-meshheading:8463253-Calcium, pubmed-meshheading:8463253-Carrier Proteins, pubmed-meshheading:8463253-Complement Membrane Attack Complex, pubmed-meshheading:8463253-Cytoplasmic Granules, pubmed-meshheading:8463253-Exocytosis, pubmed-meshheading:8463253-Flow Cytometry, pubmed-meshheading:8463253-Fluorescence, pubmed-meshheading:8463253-Humans, pubmed-meshheading:8463253-Kinetics, pubmed-meshheading:8463253-Membrane Fusion, pubmed-meshheading:8463253-Membrane Proteins, pubmed-meshheading:8463253-Phosphatidylserines, pubmed-meshheading:8463253-Phospholipid Transfer Proteins, pubmed-meshheading:8463253-Phospholipids, pubmed-meshheading:8463253-Platelet Activation, pubmed-meshheading:8463253-Staurosporine, pubmed-meshheading:8463253-Tetradecanoylphorbol Acetate
pubmed:year
1993
pubmed:articleTitle
Contribution of platelet microparticle formation and granule secretion to the transmembrane migration of phosphatidylserine.
pubmed:affiliation
Oklahoma Medical Research Foundation, Oklahoma City 73104.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.