Taurine binding to membranes from rat brain regions.

[3H]-taurine binding to membranes from different regions from rat brain was studied. Binding to membranes from cerebral cortex and its subcellular fractions, hypothalamus, olfactory bulb and cerebellum was measured. Binding to membranes from dorsal root ganglion was also determined. Na+-dependent taurine binding was consistently observed in all the membranes except those from dorsal root ganglion. A KD = 4.06 muM was obtained for binding to membranes from cerebral cortex. Na+-dependent taurine binding was displaced by 20 muM strychnine or bicuculline. Na+-dependent taurine binding with properties corresponding to a postsynaptic interaction could not be detected in any of the regions studied. The possibility of Na+-dependent taurine binding, representing binding to uptake sites or to postsynaptic receptors for GABA and glycine, is discussed.