| Objective To monitor and compare the early changes of neurotransmitter include excited amino acid ( Glu and Asp) and inhibited amino acid (Tau )in the brain after CPB and deep hypothermic circulatory arrest (DHCA) , and To valuate cerebral protection by antegrade selective cerebral perfusion (ASCP) via right axillary artery. ASCP is regarded as an assistant method in deep hypothermic circulatory arrest (DHCA) in that it provides partial brain blood flow ,maintains a low brain temperature, optimizes cerebral metabolic function during DHCA by supplying oxygen and some nutrient and removal of catabolic products; thus prolonging the limitation of safety of DHCA. But brain edema probably happens to restrict the clinical use of this method. Some protecting drugs including cerebral protective fluid is in research and some progresses have been achieved, Indications for ASCP should be strictly identified and possible risk should be prevented. Progressively to identify the effects of Tau and ASCP on early changes of excitatory amino acids (EAA) in hippocampus of Rabbit Brain due to deep hypothermic circulatory arrest (DHCA) . Method twenty four New Zealand rabbits were randomly allocated into three groups. (group I , n=8), Tau 150 mg/kg group, (group II ,n=8) ASCP group, (group III, n=8) control group. Cardiac pulmonary bypass(CPB) was set up after cerebral microdialysis model was established. High performance liquid chromatography was employed to monitor the continuous changes of glutamic acid(Glu), aspartic acid(Asp), taurine(Tau) and glycin(Gly) in the hippocampus CA1 region at anaesthesia periods, CPB stage, pre 30 minutes in DHCA, post 30 minutes in DHCA, pre 30 minutes in rewarming, post 30 minutes in rewarming. Results There was no notable changes of Glu in CPB group in all phases . Increase of Glu in group was (5.1 ± 1.5) 和 (4.1 ± 1.4) times was higher (t=3. 74, 5. 45, P<0.01) than increase of Glu in group I was (2. 1 ±1.5) 和 (1. 1±0. 4) t imes at pre 30 minutes...
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