Gangliosides of various rat tissues: distribution of ganglio-N-tetraose-containing gangliosides and tissue-characteristic composition of gangliosides.

Gangliosides were extracted from various tissues of rat (Wistar strain, male, 3 months old) and their structures were elucidated by enzymatic and chemical procedures including the analysis by negative ion fast atom bombardment mass spectrometry. All tissues analyzed contained gangliosides in various but characteristic concentrations. GD1a was detected in the various extraneural tissues (erythrocytes, buffy coat, bone marrow, testis, spleen, and liver) in amounts corresponding to more than 30% of total lipid-bound sialic acid, and surprisingly, it was the sole ganglioside found in buffy coat. The extraneural tissues were classified into several categories according to the nature of the asialo-oligosaccharides of gangliosides as follows: (1) gangliosides with ganglio-N-tetraose were exclusively present (buffy coat and erythrocytes), (2) the concentration of ganglio-N-tetraose-containing gangliosides was higher than that of lactose-containing gangliosides (testis and bone marrow), (3) ganglio-N-tetraose-containing gangliosides amounted to 25-30% of lactose-containing gangliosides (liver and spleen), (4) ganglio-N-tetraose-containing gangliosides amounted to 7-11% of lactose-containing gangliosides (lung and stomach), (5) more than 90% of gangliosides were lactose-containing gangliosides (heart, intestine, and kidney). In addition, the following gangliosides were characteristically detected in high concentration in the following tissues: GM4 in kidney. GM2 in bone marrow, fucosyl GM1 and GM1 in erythrocytes and GM3 with 2-hydroxy fatty acid, phytosphingosine and N-glycolylneuraminic acid in intestine.