Intravascular pathobiology of acetyl glyceryl ether phosphorylcholine (AGEPC), a synthetic platelet-activating factor (PAF). I. Intravenous infusion in guinea pigs.

Intravenous infusion of 1-O-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine (AGEPC), a synthetic platelet-activating factor (PAF), induced fatal anaphylactoid reaction in guinea pigs, or reversible thrombocytopenia and leucopenia. These reactions showed a maximal depression of circulating platelet and leucocyte numbers within 30 s after AGEPC infusion. Fatal reaction occurred at doses higher than 0.81 micrograms AGEPC/kg, while lower doses of AGEPC caused a reversible thrombocytopenia and leucopenia. The levels of circulating platelets and leucocytes at lower - non-fatal - doses of AGEPC, returned to pre-infusion levels within 60 min. These studies document that intravenous administration of AGEPC, into guinea pigs, initiates identical intravascular infusion of AGEPC into the rabbit and baboon, and supports the notion that the biological activity of AGEPC can cross species barriers.