大鼠脑缺血再灌流后海马氨基酸水平变化与神经元损害的关系探讨

目的探讨脑缺血再灌流后海马氨基酸递质变化与神经元损害的关系。方法建立大鼠前脑缺血再灌流模型，测定海马ＣＡ１区和ＣＡ３／齿状回区游离氨基酸含量，观察阻断隔－海马通路对海马神经元损害和氨基酸水平的影响。结果（１）海马结构中仅ＣＡ１区神经元明显损害，但ＣＡ１区和ＣＡ３／齿状回区的Ｇｌｕ、Ａｓｐ和ＧＡＢＡ含量无差异。（２）阻断隔－海马通路可明显减轻海马神经元损害，但对海马氨基酸水平变化无影响。结论脑缺血再灌流后，氨基酸递质水平的异常变化不是海马ＣＡ１区神经元选择性易损的唯一决定因素，隔－海马通路末梢释放的神经递质也参与海马神经元损害过程。

Approach to the relationship between hippocampal amino acid levels and neuronal damage after forebrain ischemia/reperfusion in rats

Objective To study the relationship between hippocampal amino acid levels and neuronal damage after cerebral ischemia/reperfusion.Methods Forebrain ischemia/reperfusion model was established in the rats.The contents of amino acids in the hippocampal CA 1 subfield and CA 3/dentate gyrus were measured.The effect of septo hippocampal deafferentation to the hippocampal neuronal damage and amino acid levels was observed.Results 1.The ischemic neuronal damage was observed only in the CA 1 subfield among the hippocampal structures.The levels of Glu,Asp and GABA in CA 1 subfield were not different from those in CA 3 subfield and dentate gyrus.2.The septo hippocampal deafferentation ameliorated the ischemic neuronal damage,but had no effect to the hippocampal amino acid levels.Conclusion The abnormal change of amino acid transmitter levels following cerebral ischemia is not the only factor that results in the selective vulnerability of CA 1 neurons to ischemia.The neurotransmitters released from the septo hippocampal terminals during cerebral ischemia also take part in the hippocampal neuronal damage.