EFFECTS OF ACETYL GLYCERYL ETHER PHOSPHORYLCHOLINE ON HUMAN-PLATELET FUNCTION-INVITRO

  • 1 January 1981
    • journal article
    • research article
    • Vol. 58  (5) , 1027-1031
Abstract
AGEPC (1-O-hexadecyl/octadecyl-2-acetyl-sn-glyceryl-3-phosphorylcholine), also known as platelet-activating factor (PAF) at 1.9 .times. 10-8 M or higher, induced concentration-dependent aggregation and release in human platelet-rich plasma. Comparative studies with arachidonate, collagen, ionophore [calcimycin] and ADP suggested that AGEPC was a strong stimulus for platelet aggregation and probably a moderate agonist for release and a relatively weak inducer of TX[thromboxane]A2 production. The initial phase of AGEPC-induced aggregation was independent of ADP release and TXA2 formation, since it was not inhibited by ASA [aspirin], apyrase or CP/CPK [Creatine phosphate/creatine phosphokinase]. Irreversible aggregation always required ADP release, TXA2 formation was not essential in each instance. In several experiments, full aggregation responses took place in AGEPC-stimulated platelets that were pretreated with ASA. AGEPC-induced release of 5-HT [serotonin], .beta.-thromboglobulin and PF[platelet factor-4]-4 occurred in parallel and were inhibited by both apyrase and ASA. Washed human platelets did not respond to exogenous AGEPC in the absence of ADP and did not appear to generate significant quantities of AGEPC upon stimulation with thrombin or ionophore.