Does de novo synthesis of lysophosphatidylcholine occur in rat lung microsomes?

Abstract

Incubation of rat lung microsomes with CDP[Me-14C]choline resulted in formation of radioactive lysophosphatidylcholine and phosphatidylcholine. Evidence is provided which suggests that lysophosphatidylcholine formation cannot be ascribed completely to phospholipase A degradation of phosphatidylcholine. Lysophosphatidylcholine production can be stimulated by addition of monoacylglycerol or diacylglycerol. It is suggested that diacylglycerol is partly hydrolyzed to monoacylglycerol and subsequently converted to lysophosphatidylcholine. A direct transfer of phosphocholine from CDPcholine to monoacylglycerol is demonstrated by equimolar incorporation of 1(3)-[9,10-3H2]palmitoylglycerol and phospho[Me-14C]choline into lysophosphatidylcholine.