Human placental lipid metabolism. III. Synthesis and hydrolysis of phospholipids.

Both diacyl GPC (glycerylphosphorylcholine) and diacyl GPE (glycerylphosphorylethanolamine) are synthesized in human placental tissue from their respective monoacyl precursors. The origin of the monacyl phosphatides is apparently not the result of placental phosphatide acyl-hydrolase activity. The most likely source is maternal serum. The declining level of 1-acyl GPC in maternal serum is not attributable to lysophosphatide acylhydrolase activity and is probably explained by placental utilization for the synthesis of diacyl GPC.