[Determination of gamma-aminobutyric acid and glutamate in human gastric mucosa by high performance liquid chromatography].

A method for analysis of gamma-aminobutyric acid (GABA) and glutamate (Glu) in human gastric mucosa by high performance liquid chromatography (HPLC) was developed. A gradient elution was used for the separation and quantification of GABA and Glu after pre-column derivatization with phenylisothiocyanate (PITC). The column was Pico x Tag for free amino acids. GABA and Glu were determined with UV detector at 254 nm. Good linearities were observed within the ranges from 0.125 to 6.25 micromol/L for GABA and from 0.025 to 2.5 mmol/L for Glu. The average recoveries were 95.4% for GABA and 93.5% for Glu. The intra- and inter-precision values were within 3.56% and 7.47% for GABA, and 1.12% and 5.98% for Glu, respectively. The method is sensitive, specific and accurate. It can be used in the determination of GABA and Glu in human gastric mucosa tissue. The concentrations of GABA and Glu in cancer tissues are significantly higher than those in normal tissue.