Choline biosynthesis by a preparation enriched in synaptosomes from rat brain

Abstract
Various preparations of mammalian brain contain enzymes, the phosphatidylethanolamine N-methyltransferases (PeMT), catalyze the synthesis of phosphatidylcholine (PC), using S-adenosylmethionine as a methyl donor for the stepwise methylation of phosphatidylethanolamine. The highest specific activity of PeMT was present in synaptosomal preparation. Rat brain synaptosomal preparations can also metabolize the PC generated by PeMT to liberate free choline for acetylcholine and membrane biosynthesis.