Receptors and Enzymes for Medical Sensing of L-Glutamate

Medical sensing systems using isolated or intact glutamate receptor (GluR) ion channels and glutamate oxidase (GluOx) are discussed for L-glutamate, one of the principal neurotransmitter in the central nervous systems of mammalian brain, and related agonists. The GluR-based sensing system used for the evaluation of signal transduction ability of GluR channels demonstrate that the agonist selectivity based on the signal transduction ability is not parallel to that of the binding assay. On the other hand, the appropriate design of the enzyme system, namely glutamate oxidase (GluOx), in combination with horseradish peroxidase (HRP), enables to real-time monitoring of L-glutamate in vivo and in vitro and also to visualize its release in submerged, acute mouse hippocampal slices.