A high performance liquid chromatography/electrochemical assay for glutamatergic neurotransmitters in the rat brain

✍ Scribed by L. G. Harsing Jr.; A. Lajtha; E. S. Vizi

• Publisher: John Wiley and Sons
• Year: 1989
• Tongue: English
• Weight: 348 KB
• Volume: 3
• Category: Article
• ISSN: 0269-3879
• DOI: 10.1002/bmc.1130030410

✦ Synopsis

The release and content of the excitatory amino acid neurotransmitters glutamate and aspartate in rat striatum were determined by liquid chromatography/electrochemistry. This determination was based on precolumn off-line derivatization of the amino acids with o-phthaldialdehyde and 2-mercaptoethanol (OPT/2-MCE), and the adducts formed were separated under isocratic conditions and oxidized on a glassy carbon electrode at moderate potential (+0.6 V). The standard and the extracted glutamate when derivatized with OPT/2-MCE produced similar electrochemical and chromatographic characteristics. The detection limit of glutamate was 0.5 pmol. Depolarization induced by the high potassium medium (40 mmol/L) enhanced the release of glutamate and aspartate from superfused rat striatum, whereas the efflux of glutamine remained unchanged. Perfusion (for 60-70 min) removed 50-80% of the free amino acid content of striatal tissue. The method described here is useful in neurochemical investigations of the brain amino acid neurotransmitters.