Gangliosides of human, cat, and rabbit spinal cords and cord myelin

Gangliosides were isolated from whole spinal cords and cord myelin of human, cat, and rabbit by a revised methodology. The method included the sequential application of DEAE-Sephadex column chromatography, base treatment, Sephadex G-50 column chromatography, and finally Iatrobeads column chromatography. The human whole spinal cord was found to contain about one-tenth of the ganglioside concentration of that in cerebral gray matter and about one-third of that in cerebral white matter. Low levels of gangliosides were also found in cat and rabbit whole cords. Only N-acetylneuraminic acid could be detected in the ganglioside fractions of all three species. The whole cords also possessed unique ganglioside patterns when compared with the patterns of cerebral tissues. The most prominent and consistent features were the reduced concentration of GD1a and increased amounts of GM3 and GD3. Human, but not cat and rabbit, spinal cord also contained GM4 as one of the major gangliosides. Myelin prepared from the spinal cords of all three species also contained gangliosides. The amounts were only about half of those in the respective cerebral white matter myelin. The cord myelin ganglioside pattern was generally similar to the cerebral white matter myelin within the same species. GM1 was the most abundant ganglioside in the cord myelin. GM4 was found to be highly enriched only in myelin prepared from human sources.