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本文用ＨＲＰ追踪与免疫细胞化学结合法和免疫电镜技术研究了脊髓背角的ＧＡＢＡ神经元的分布、ＧＡＢＡ能末梢的来源及其超微结构联系。结果表明：在脊髓背角Ⅰ～Ⅵ层内均有ＧＡＢＡ神经元胞体和纤维分布，其中Ⅰ～Ⅲ层较为密集，在后外侧束内也存在ＧＡＢＡ能纤维及胞体。脊髓背角的ＧＡＢＡ能神经末梢有３个来源：①延髓的大缝核、隐缝核、苍白缝核及腹侧网状结构的ＧＡＢＡ能神经元；②脊髓固有的ＧＡＢＡ能神经元；③脊神经节的ＧＡＢＡ能神经元。ＧＡＢＡ能末梢可作为突触前成分或突触后成分与未标记末梢形成轴－树突触，也可同时作为突触前、后成分而形成轴－树型自调节突触。结果提示突触前的ＧＡＢＡ能末梢可能对脊髓背角内的其它神经元起抑制和脱抑制作用；同时背角内ＧＡＢＡ能神经元还接受其它神经元的调控。
In this paper, HRP tracing and immunocytochemistry and immunoelectron microscopy were used to study the distribution of GABA neurons in spinal dorsal horn and the origin and ultrastructure of GABAergic terminals. The results showed that there were GABA neuronal cell bodies and fiber distribution in Ⅰ ~ Ⅵ layers of spinal dorsal horn, in which Ⅰ ~ Ⅲ layers were more dense, GABA fibers and cell bodies were also present in the posterior lateral bundle. There are three sources of GABAergic nerve endings in the dorsal horn of the spinal cord: GABAergic neurons in the medulla oblongata, cryptococcycia, paleotape, and ventral reticular structures; ② GABAergic neurons in the spinal cord; ③ spinal nerves GABAergic neurons. GABAergic terminals can form axonal-dendritic synapses as pre-synaptic or post-synaptic components and unlabeled terminals, but also act as axon-tree self-regulating synapses at the presynaptic and posterior components simultaneously. The results suggest that pre-synaptic GABAergic terminals may inhibit and desensitize other neurons in spinal dorsal horn. Meanwhile, GABAergic neurons in dorsal horn may also be regulated by other neurons.