ACETYL GLYCERYL ETHER PHOSPHORYLCHOLINE - INTRAVASCULAR ALTERATIONS FOLLOWING INTRAVENOUS-INFUSION INTO THE BABOON

Abstract

I.v. infusion of 1-O-hexadecyl/octadecyl-2-acetyl-sn-glyceryl-3-phosphorylcholine (AGEPC) in baboons (28 .mu.g/kg) induced acute but reversible, thrombocytopenia and neutropenia and the intravascular release of platelet factor 4 and thromboxane B2. Maximal depression of circulating platelets and neutrophils occurred within 30 s after AGEPC infusion and was accompanied by significant elevations in plasma platelet factor 4 and thromboxane B2 levels (P < 0.02). Hematocrit values increased after AGEPC infusion but this was delayed relative to the other intravascular alterations maximal hematocrit values occurred at 10-20 min after AGEPC infusion. Thrombocytopenia induced by AGEPC was reversed within 2-3 min; circulating neutrophils did not return to preinfusion levels until 30 min after AGEPC infusion. Plasma platelet factor 4 and thromboxane B2 elevations gradually decreased and returned to preinfusion levels within 30-60 min. The deacetylated derivative of AGEPC, lyso-glyceryl ether phosphorylcholine, had no effect when similarly infused into baboons. I.v. administration of AGEPC into baboons initiated significant but reversible intravascular alterations; this unusual acetylated alkyl phosphoglyceride may be an important mediator of inflammation in primates, including man.