High-performance thin-layer chromatography and densitometric determination of brain ganglioside compositions of several species

Abstract

Improved resolution of complex brain ganglioside mixtures was achieved by high-performance thin-layer chromatography. The percentage distribution of individual gangliosides was then determined by direct densitometric seanning, employing a transmittance mode, of the resorcinol-positive spots on the plate. As little as 90 pmol (29 ng) of lipid-bound sialic acid could be detected with a good signal-to-noise ratio. A linear detector response was observed up to 3.0 μg of lipid-bound sialic acid. The brain white matter ganglioside patterns of eight animal species, including human, chimpanzee, monkey, chicken, bovine, sheep, and pig, were examined in detail. In addition, human brain gray matter, rat cerebral, rat brain gray matter, and rat cerebellar ganglioside patterns were also studied. Ganglioside G M4 (G 7) was found to be one of the major components in primate and chicken brain white matter, but it represented only a minor ganglioside in other species. Other major gangliosides in all brain samples studied were G M1, G D1a, G D1b, and G T1b. G M1 was more abundant in white matter than in gray matter. G T1a, a recently discovered ganglioside species, was found in all species examined, but was most abundant in the rat cerebellum. The latter source also contained high proportions of G T1b and G Q1b.