Objective:To investigate the effect of hypothermia on amino acid neurotransmitters in gerbil models of unilateral cerebral ischemia.Methods:Sixteen Mongolian gerbils were randomly subjected to unilateral internal carotid artery occlusion under conditions of either 37℃ or 32℃ for 30 min.Hippocampal concentrations of glutamate ,glycine and GABA were monitered using in vivo microdialysis combined with high performance liquid chromatography.Results:Hypothermia significantly inhibited the release of glutamate and glycine,therefore the high excitotoxic index seen in the normothermic group was strikingly decreased in the hypothermic group.Conclusion:The neuroprotective effect of hypothermia on cerebral ischemia may reside , in part , in its ability to decrease extracellular excitotoxic indexes.