Separation of lipids from lactate in experimental allergic encephalomyelitis by zero quantum NMR techniques

Using localized proton spectroscopy, the author and associates previously have observed an increase in the resonance at 1.2 +/- 0.2 ppm in the brain of monkeys with experimental allergic encephalomyelitis (EAE). In proton nuclear magnetic resonance (NMR) spectroscopy, the lactate methyl protons resonate at dose to the same chemical shift frequency as the lipid methylene protons (1.2 +/- 0.2 ppm). Noninvasive zero quantum NMR techniques were used to separate lipids from lactate in the brain during the course of EAE development. Out of 53 zero quantum NMR measurements (from three animals), 16 measurements were made at a time when a resonance at 1.2 ppm appeared (after the animals developed EAE). In all these cases, lactate was not detectable. The fact that the resonance (identified as lipids with zero quantum techniques) correlated with histochemical Oil red O staining suggests that these mobile NMR signals are associated with demyelination.