Studies on molecular species of choline and ethanolamine glycerophospholipids obtained from rat brain myelin and synaptosomes by gas-liquid chromatography mass spectrometry.

By converting to t-butyldimethylsilyl derivatives, molecular species of ethanolamine glycerophospholipid including both 1,2-diacyl and 1-alk-1'-enyl-2-acyl (plasmalogen) types were able to be analysed by a gas chromatography mass spectrometry selected ion monitoring technique. The samples analysed were ethanolamine glycerophospholipid and also choline glycerophospholipid obtained from myelin and synaptosomes of rat brain, both of which are characteristic subcellular organella of the nervous system. Main molecular species of ethanolamine glycerophospholipid were as follows: in myelin as 1,2-diacyl type, 36:1 (mainly 18:0/18:1), and as 1-alk-1'-enyl-2-acyl type, 34:2 (mainly vinyl 16:0/18:1), 36:2 (mainly vinyl 18:0/18:1) and 36:3 (mainly vinyl 18:1/18:1), whereas in synaptosomes as 1,2-diacyl type 36:1 (mainly 18:0/18:1), 38:4 (mainly 18:0/20:4) and 40:6 (18:0/22:6), and as 1-alk-1'-enyl-2-acyl type 34:2 (mainly vinyl 16:0/18:1), 36:2 (mainly vinyl 18:0/18:1), and 36:3 (mainly vinyl 18:1/18:1). The molecular species of choline glycerophospholipid consisted almost entirely of 1,2-diacyl type and they were in myelin 34:1 (mainly 16:0/18:1), 36:1 (mainly 18:0/18:1) and 36:2 (mainly 18:1/18:1), whereas in synaptosomes 32:0 (mainly 16:0/16:0), 34:0 (16:0/18:0), 34:1 (mainly 16:0/18:1) and 36:1 (mainly 18:0/18:1). In myelin as 1-alkyl-2-acyl type, 34:1 (1-hexadectl-2-octadecenoyl) was present at about 7%.