THE ANALYSIS OF EXCITATORY, INHIBITORY AND OTHER AMINO-ACIDS IN RAT-BRAIN MICRODIALYSATES USING MICROBORE LIQUID-CHROMATOGRAPHY

Three microbore liquid chromatography (LC) assays for determination of amino acids in rat brain dialysates are described: one for separation of amino acids by gradient elution and electrochemical detection, one for analysis of GABA by isocratic elution and electrochemical detecti on, and one for fast measurement of glutamate and aspartate by gradien t elution and fluorescence detection. The assays are reliable, reprodu cible and sensitive. In comparison with conventional LC, a 5-fold incr ease in sensitivity was obtained for GABA. Optimization of the derivat ization chemistry and the microbore LC system are discussed, as well a s important practical aspects.