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为了探讨神经递质在癫痫发病机理中的作用，用包埋前免疫电镜双标法研究了正常大鼠海马ＣＡ_１，区谷氨酸（Ｇｌｕ）神经元与ＧＡＢＡ神经元之间的突触联系。先用ＤＡＢ为呈色剂显示ＧＡＢＡ免疫反应，然后以钼酸铵－ＴＭＢ法显示Ｇｌｕ免疫反应，再进行免疫电镜包埋。观察发现：在海马ＣＡ_１区锥体细胞层有许多Ｇｌｕ免疫反应阳性神经元；在锥体细胞层、多形层和辐状层可见一些ＧＡＢＡ免疫反应阳性神经元，胞体为锥体或多角形。在多形层还可见ＧＡＢＡ阳性树突与Ｇｌｕ阳性轴突形成对称性树－轴突触，在辐状层可见ＧＡＢＡ阳性轴突与Ｇｌｕ阳性树突形成对称性轴－树突触。此外，在多形层和辐状层内尚可见到Ｇｌｕ阳性轴突与Ｇｌｕ阳性树突之间形成对称性轴－树型自调节突触，ＧＡＢＡ阳性轴突之间形成对称性和非对称性轴－轴型自调节突触。上述结果首次证实在海马ＣＡ_１区兴奋性Ｇｌｕ神经元与抑制性ＧＡＢＡ神经元之间存在着复杂的突触联系，从而为不同神经递质参与癫痫发病机理提供了超微结构依据。
In order to investigate the role of neurotransmitters in the pathogenesis of epilepsy, the synaptic connections between CA1, glutamate (Glu) neurons and GABA neurons in hippocampus of normal rats were studied by immunohistochemical double-labeling before embedding. GABA immunoreaction was first displayed by DAB as a color former, then Glu immunoreactivity was revealed by ammonium molybdate-TMB method, and then immunoelectron microscopy was used for embedding. It is observed that there are many Glu immunoreactive neurons in the hippocampal CA1 pyramidal cell layer; some GABA immunoreactive neurons are visible in the pyramidal, pleomorphic and radial layers, and the cell bodies are pyramidal or polygonal. In the pleomorphic layer, GABA-positive dendrites and Glu-positive axons can also form symmetrical tree-axon synapses. In the radial layer, GABA-positive axons and Glu-positive dendrites form symmetric axonal-dendritic synapses. In addition, symmetric axis-tree self-regulating synapses were formed between Glu-positive and Glu-positive dendrites in both the pleomorphic and radial layers, with symmetry and asymmetry between the GABA-positive axons Shaft-axis self-regulating synapse. The above results for the first time confirmed the existence of complex synaptic connections between excitatory Glu neurons and inhibitory GABA neurons in the hippocampal CA1 region, thus providing an ultrastructure basis for the involvement of different neurotransmitters in the pathogenesis of epilepsy.