Demonstration of taurine-like immunoreactive structures in the rat brain.

An antiserum was raised in a rabbit by immunization with taurine bound to bovine serum albumin. The antibody was purified by passage over an immunoabsorbent column (formyl-cellulofine-taurine) and it did not cross-react significantly with glutamate, aspartate, glycine, GABA (0.4%), glutamine, proline, cysteine, beta-alanine, cysteic acid, carnosine or homocarnosine in enzyme-linked immunosorbent assays and nitrocellulose paper immunoblots. Immunocytochemical studies employing the peroxidase-antiperoxidase immunohistochemical technique revealed that many cerebellar Purkinje cells showed taurine-like immunoreactivity. Labelled axons could be followed within the white matter up to the deep cerebellar nuclei, where numerous puncta were observed. Immunoelectron microscopic examination revealed that labelled puncta were presynaptic terminals, and axo-dendritic or axo-somatic symmetrical synapses were observed on deep cerebellar nuclear neurons.