Abstract: A simple and effective coupling of microdialysis and capillary electrophoresis with laser induced fluorescence detection technique was applied to the analysis of amino acid neurotransmitters in hypothalamus of rat after an acute exhausting exercise. The separation of amino acids was achieved by using an uncoated fused silica capillary(57 cm×75 μm i.d.) with a buffer of 10 mmol/Ldisodium tetraborate at pH 10 and an applied voltage of 12.5 kV. The detection limit was 10^-10 mol/Lfor each amino acid. It is sufficiently sensitive and rapid for the determination of amino acid in 5μL Microdialysate. In comparison to pre-exercise, a significant increase in the levels of 6 hypothalamic amino acids(arginine, glycine, lysine, glutamic acid, alanine, γ-amino-n-butyric-acid) after exercise was found. These results demonstrate that increase of metabolic amino acids in hypothalamus of rats can be induced by exhaustive exercise and suggesting that amino acid neurotransmitters may play functional roles in the central effects of exercise.

Key words: Microdialysis, Amino acid neurotransmitter, Exercise