Endogenous sulphur-containing amino acids: potent agonists at presynaptic metabotropic glutamate autoreceptors in the rat central nervous system

摘要

We have recently demonstrated that presynaptically located metabotropic glutamte(mGlu) autoreceptors regulate synaptic glutamate release both in vitro and in vivo. We now report a positive modulatory action of the sulphur-containing amino acids(SCAAs), L-cysteic acid(CA)and L- cysteine sulphinic acid(CSA), at presynaptic group I mGlu receptors, specifically of the mGlu5 subtype, acting to enhance synaptic glutamate release from the rat forebrain in vitro. Neuronal glutamate release was monitored using electrically-evoked efflux of preloaded[~3H]-D- Aspartate from rat forebrain hemisections.