Ganglioside GD1b disodium salt (bovine brain) may act as a bacterial toxin receptor (tetanus, botulinus); high levels are found in gliomas and astrocytomas. Gangliosides are major constituents of neuronal cell membranes and endoplasmic reticulum and have been shown to modulate cell signal transduction. Gangliosides are more complex glycosphingolipids because oligosaccharide chains which have N-acetylneuraminic acid (NeuNAc) are attached to a ceramide.