In vivo microdialysis in the visual cortex of awake cat: II: Sample analysis by microbore HPLC–electrochemical detection and capillary electrophoresis–laser-induced fluorescence detection

Abstract

Sampling and monitoring release of excitatory and inhibitory amino acids in the striate cortex of mammals will provide important information for visual system research. Two microbore high performance liquid chromatography–electrochemical detection methods and a capillary electrophoresis–laser induced fluorescence detection were developed to determine the inhibitory amino acid, γ-aminobutyric acid and the excitatory amino acids, glutamate and aspartate in microdialysates of cat striate cortex. In the liquid chromatography method, samples were derivatized using OPA–TBT. Ten microliters of derivatized product was injected onto the microbore column (100×1 mm i.d., C8) for quantitative analysis. Electrochemical detection was employed. In the capillary electrophoresis method, samples were derivatized using fluorescein isothiocyanate and separated in borate buffer within 15 min, then detected by a laser-induced fluorescence detector.