Uptake and metabolism of polyene phosphatidylcholine in rat brain

The rate and mechanism of incorporation of polyene phosphatidylcholine (PPC) and lysophosphatidylcholine into rat brain have been studied with double labelled substrates administered intravenously. It was found that both substances could be taken up into the brain with transfer velocities of the order: lysophosphatidylcholine much greater than phosphatidylcholine greater than glycerophosphocholine. Similarities between the 3H/14C ratios of the substrates and the brain phosphatidylcholine, together with retention of the label in the original acyl moieties, as demonstrated by phospholipase A2 hydrolysis, gave conclusive proof that both PPC and lysophosphatidylcholine are taken up intact into the brain.