Metabolic Studies on Ethanolamine Phosphoglycerides in Neuronal and Glial Cells

Abstract

Marked differences in phospholipid metabolism have been observed between glial and neuronal cell enriched fractions. Recently, evidence was obtained for a faster turnover of glycerophospholipids in neurons than in glial cells, since neurons contained a considerably higher phospholipase A₁ and A₂ activity when compared to the glial cell enriched fraction (Woelk et al., 1973). Furthermore the neuronal cell bodies were found to possess a much higher rate of exchange of both serine and ethanolamine into the phospholipids than the glial cell enriched fraction (Goracci et al., 1973) and Freysz et al., (1969), showed in their extensive investigation on the kinetics of the biosynthesis of phospholipids in neurons and glial cells, isolated from rat brain cortex, that neuronal phospholipids had a faster turnover than glial phospholipids. Recent results, presented by Woelk et al. (1974), indicated that phosphatidylinositol and phosphatidylcholine had the fastest and ethanolamine plasmalogen the slowest turnover in both cell populations.