Quantification and fatty acid and fatty aldehyde composition of ethanolamine, choline, and serine glycerophosphatides in human cerebral grey and white matter*

The quantities of ethanolamine glycerophosphatides (EGP), choline glycerophosphatides (CGP), and serine glycerophosphatides (SGP) were determined in the grey and white matter from three apparently normal adult human brains. In each locale the quantities decreased from EGP through CGP to SGP. The quantities of aldehydes in these lipids were also determined. In grey matter the aldehyde content (expressed as per cent of fatty acids plus aldehydes) of EGP, CGP, and SGP was 22, 0.3, and 0.2% respectively; while in white matter the proportions were 49, 0.8, and 13%, respectively. Palmitaldehyde, stearaldehyde, and olealdehyde made up 90% of the aldehydes found. White matter glycerophosphatides contained much more olealdehyde than those from grey matter. EGP and SGP contained much larger proportions of C20 and C22 polyenoic acids from grey matter than from white matter. CGP, on the other hand, had a similar fatty acid composition, comprised mainly of 16:0, 18:0, and 18:1 acids, in each locale. The differences in fatty acid composition of these three glycerophosphatides may be related to the higher myelin content of white matter.