A high performance liquid chromatography/electrochemical assay for glutamatergic neurotransmitters in the rat brain.
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.
Harsing
L G
LG
Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest.
Lajtha
A
A
Vizi
E S
ES
D000818:Animals; D001224:Aspartic Acid / Q000032:analysis; D001923:Brain Chemistry; D002851:Chromatography, High Pressure Liquid; D003342:Corpus Striatum / Q000032:analysis; D004563:Electrochemistry; D005971:Glutamates / Q000032:analysis*; D018698:Glutamic Acid; D005973:Glutamine / Q000032:analysis; D008297:Male; D018377:Neurotransmitter Agents / Q000032:analysis*; D051381:Rats; D011919:Rats, Inbred Strains
D005971:Glutamates; D018377:Neurotransmitter Agents; D005973:Glutamine; D001224:Aspartic Acid; D018698:Glutamic Acid