Platelet phosphatidylserine exposure and procoagulant activity in clotting whole blood: different effects of collagen,TRAP and calcium ionophore A23187
2003 (English)In: Thrombosis and Haemostasis, ISSN 0340-6245, Vol. 89, no 1, 132-141 p.Article in journal (Refereed) Published
We have studied the effects of different platelet agonists onphosphatidylserine (PS) exposure and clotting times in bloodwithout anticoagulants. Similar reductions in clotting time wereobtained for collagen, TRAP-6 or calcium ionophore A23187(50 µmol/L), in spite of huge differences in PS expression[6.7 ± 2.4%, 2.3 ± 0.5% and 99.9 ± 0.1%, respectively (mean ±SD, n = 5)]. Furthermore, the clotting times were much longerfor samples with A23187 exposing the same amounts of PS assamples with collagen or TRAP-6. Annexin V reversed theclotting time reduction, but could not prevent coagulation.Addition of phospholipid vesicles containing 20% PS neitheraffected the clotting times nor induced clotting in recalcified,platelet-free plasma.We conclude that platelet PS exposure is necessary, but notsufficient, for the coagulation amplification observed whenplatelets are stimulated via physiological receptors in a wholeblood environment.
Place, publisher, year, edition, pages
2003. Vol. 89, no 1, 132-141 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-25245Local ID: 9684OAI: oai:DiVA.org:liu-25245DiVA: diva2:245573