Changes in amino acid neurotransmitters during cerebral ischemia and reperfusion in awake rats / 中国病理生理杂志

ABSTRACT

AIM: To study the dynamic changes of amino acid neurotransmitters during cerebral ischemia and reperfusion in awake rats. METHODS: Model of cerebral ischemia and reperfusion in awake rats was replicated. Glutamate (Glu), aspartate (Asp), ?-aminobutyric acid (GABA), glycine (Gly), taurine (Tau), alanine (Ala), serine (Ser), threonine (Thr) and glutamine (Gln) concentrations were measured with microdialysis, and excitotoxic index (EI) was calculated in dialysates of hippocampus, neo-cortex and striatum. RESULTS: The significant increases in extracellular not only excitatory amino acid neurotransmitters-Glu and Asp, and their neuromodulator-Gly, but also inhibitory amino acid neurotransmitter-GABA and its neuromodulator-Tau and Ala were observed. However, the EI, representing the balance of excitatory and inhibitory neurotransmitters, was significantly increased during ischemia. CONCLUSION: The results suggest that the elevated Glu and Asp levels during ischemia are insufficient to independently engender ischemic damage, and other neurotransmitters or other factors may play an important role in modulating the excitotoxic effects of Glu and Asp.