Glycoprotein IIb/IIIa blockade inhibits platelet aminophospholipid exposure by potentiating translocase and attenuating scramblase activity.
2007 (English)In: Cellular and Molecular Life Sciences (CMLS), ISSN 1420-682X, E-ISSN 1420-9071, Vol. 64, no 7-8, 999-1008 p.Article in journal (Refereed) Published
The present study investigated the mechanisms underlying the inhibition of platelet phosphatidylserine (PS) exposure by GPIIb/IIIa blockade. Platelet PS exposure induced by thrombin stimulation was cell-cell contact dependent. GPIIb/IIIa blockade by c7E3 or SR121566 inhibited thrombin-induced platelet PS exposure. Thrombin stimulation induced mild, while A23187 induced extensive platelet-derived microparticle (PDMP) generation. Thrombin-induced PDMP generation was not inhibited by GPIIb/IIIa blockade. Aminophospholipid translocase activity was reduced upon platelet activation by thrombin. The reduction of non-PS-exposing platelets was attenuated by GPIIb/IIIa blockade, while little translocase activity was seen in PS-exposing platelets. Thrombin increased scramblase activity slightly in non-PS-exposing platelets, which was inhibited by GPIIb/IIIa blockade, and markedly enhanced scramblase activity in PS-exposing platelets. Activation of platelet calpain and caspase-3 or cytosolic calcium mobilization were not altered by GPIIb/IIIa inhibition. Thus, GPIIb/IIIa blockade inhibits platelet PS exposure by enhancing translocase activity and attenuating scramblase activity, but does not inhibit PDMP generation.
Place, publisher, year, edition, pages
2007. Vol. 64, no 7-8, 999-1008 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-207145DOI: 10.1007/s00018-007-6546-8PubMedID: 17372676OAI: oai:DiVA.org:uu-207145DiVA: diva2:646921