31P NMR detection of mobile dog brain phospholipids

Abstract

The in vivo dog brain ³¹P NMR spectrum has a large peak in the phosphodiester region accounting for more than 35% of the total observable phosphorus metabolites. It is possible to reduce the intensity of this peak by off‐resonance saturation. To characterize the nature of this peak, extracts of dog brain frozen in situ were analyzed by high resolution ³¹P NMR. ATP, phosphocreatine, inorganic phosphate, and phosphomonoesters were recovered in appropriate amounts in the methanol: HCI extract. However, acid soluble phosphodiesters accounted for only 8% of the observable phosphorus. More NMR observable phosphodiesters were selectively recovered following CHCI₃:methanol extraction of phospholipids. These results suggest that the in vivo phosphodiester resonance has substantial contributions from a fraction of mobile brain phospholipids. © 1986 Academic Press, Inc.