Cysteine Sulfinic Acid in the Central Nervous System: Antagonistic Effect of Taurine on Cysteine Sulfinic Acid-Stimulated Formation of Cyclic AMP in Guinea Pig Hippocampal Slices

The stimulatory effect of cysteine sulfinic acid on cyclic AMP formation was examined in slices from three different regions of guinea pig brain. The inhibitory effect of taurine on the stimulated formation of cyclic AMP was also studied. Cysteine sulfinic acid (1--10 mM) greatly increased the cyclic AMP level in striatal, cortical, and especially hippocampal slices. In hippocampal slices, taurine (0.1--30 mM) markedly lowered the increase of cyclic AMP induced by cysteine sulfinic acid, but not that induced by glutamate or aspartate. In this region, taurine also reduced the stimulatory effects on cyclic AMP formation of adenosine, norepinephrine, and histamine, but not of depolarizing agents. It did not, however, inhibit the effects of any of these stimulants in cortical slices. These results suggest that sulfur-containing amino acids, such as cysteine sulfinic acid and taurine, regulate the cyclic AMP level in the hippocampus.