Thromboxane B2 (TxB2) release following acetyl glyceryl ether phosphorylcholine (AGEPC) infusion in the rabbit

Intravenous infusion of acetyl glyceryl ether phosphorylcholine (AGEPC) into rabbits resulted in an AGEPC dose-dependent elevation of plasma thromboxane B2 (TxB2) levels within 30 seconds. In contrast to AGEPC, the deacetylated derivative, lyso-GEPC (36.8 micrograms), did not increase intravascular TxB2 levels when similarly infused into rabbits. Intravascular TxB2 levels were maximal at 60 seconds after the infusion of 0.61 micrograms AGEPC whereas at higher doses of AGEPC (1.21-2.4 micrograms), plasma TxB2 levels were maximally elevated within 30 seconds after initiation of AGEPC infusion. These acute increases in the intravascular levels of TxB2 were accompanied by the development of thrombocytopenia, neutropenia, and basopenia which occurred concomitantly with AGEPC dose-dependent elevations in the plasma levels of platelet factor 4. Elevations in the plasma TxB2 levels returned to pre-infusion levels within 10-20 minutes after the initiation of AGEPC infusion. Thus, in vivo, one potent phospholipid, AGEPC, stimulates the production of another class of potent lipid mediators, the thromboxanes.