Simultaneous monitoring multiple neurotransmitters and neuromodulators during cerebral ischemia/reperfusion in rats by microdialysis and capillary electrophoresis

In this work, focal cerebral ischemia/reperfusion was induced by the model of middle cerebral artery occlusion. The dialysates of extracellular fluid in hypothalamus were obtained by using brain microdialysis technique. An efficient and sensitive chiral capillary electrophoresis with laser-induced fluorescence detection procedure was developed for the simultaneous determination of multiple amino acids neurotransmitter including Arg, Lys, Trp, GABA, l-Ser, Ala, Tau, Gly, Glu and Asp; catcholamine (dopamine) and neuromodulator (d-Ser and O-phosphoethanolamine) in microdialysate. Different parameters that influenced CE separation were optimized. The optimal method was used to investigate the dynamic changes of neurotransmitters and neuromodulators during cerebral ischemia/reperfusion. The results indicated that extracellular levels of multiple neurotransmitters and neuromodulators were elevated during cerebral ischemia/reperfusion. The dynamic changes and functional status of releasable neurotransmitters and neuromodulators during ischemia/reperfusion were discussed.