Conversion of 3H-PAF acether by rabbit platelets is independent from aggregation: evidences for a novel metabolite.

3H-PAF-acether (Alkyl-[1', 2'-3H]- 2-acetyl-sn-glyceryl-3-phosphorylcholine) was time-dependently transformed by plasma-free rabbit platelets into an unknown product, "PX", which was distinct from lyso-PAF-acether. This effect was specific for platelets since plasma only converted 3H-PAF-acether into lyso-3H-PAF-acether and platelets were not effective in metabolizing lyso-3H-PAF-acether. Platelet aggregation did not interfere with the formation of "PX". The latter is a novel platelet metabolite of PAF-acether with as yet unknown biological properties.