[Melatonin decreases the release of amino acid transmitters in hypoxic rat cortical slice]

To study the effect of melatonin on changes in amino acid release following hypoxic stimulation, a RP-HPLC fluorometric method was used to measure the content of amino acids in the culture medium of rat brain slices. Hypoxic condition was instituted by a gas of 91.6% N2 and 8.4% O2. The results showed that the contents of amino acids, including aspartate, glutamate, glutamine, glycine, taurine and GABA, in the medium were significantly increased to 240.4%, 334.3%, 200.6%, 210.4%, 168.6% and 263.9%, respectively (P < 0.01 vs control) by 30 min hypoxic incubation. Melatonin can significantly reduce the increase of aspartate and glutamate, to 55.1% and 57.0% of the hypoxic group.