大鼠脊髓胶状质内GABA能神经元突触联系的超微结构研究

本文用免疫电镜方法对脊髓胶状质内ＧＡＢＡ能神经元的突触联系进行了超微结构研究。结果表明；脊髓胶状质内有许多ＧＡＢＡ能神经元胞体和末梢分布；标记的ＧＡＢＡ能神经末梢可作为突触前成分与未标记的ＧＡＢＡ形成输一树突触。未标记的末梢可与标记的ＧＡＢＡ末梢形成输一轴突触。此外，标记的ＧＡＢＡ能神经末梢还可作为突触前成分与标记的ＧＡＢＡ能轴突、树突或胞体形成输－轴、轴－树或轴－体突触，即自调节突触。上述结果揭示：ＧＡＢＡ能末梢可对脊髓胶状质内其它神经元产生抑制或脱抑制作用。值得注意的是胶状质内含ＧＡｎＡ的神经结构可形成各种形式的自调节突触，并借此实现其对脊髓功能的复杂调节。

ULTRASTRUCTURAL STUDIES ON THE SYNAPTIC CONNECTIONS OF GABA-ERGIC NEUROUS IN THE SUBSTANTIA GELATIONSA OF SPINAL CORD IN RATS

The synaptic connections of GABA-ergic neurons in the substantia gelationsa of spinalcord in rats were ultrastructually studied by means of iminunoelectron microscopic method.The results showed that there were numerous GABA positive somata and terminals in sub$tantia gelationsa of the spinal cord. Labeled GABA-ergic terminals served as presynaptic elemints bud formed axo-dendritic synapses with unlabeled terminils. Unlabeled terminalsserved as presynaptic elements and formed axo-axonic synapses with labeled GABA-ergicterminals. In addition, GABA-ergic terminaLs might serve as presynaptic or postsynaptic elements formed axo-axonic, axo-dendritic or axo-somatic synapses with labeled GABA-ergicstructures., i. e. autoregulatory synapes. The above mentioned results suggested that presynaptic GABA-ergic terminals might inhibit or disinhibit other neurous in the substantia gelationsa. It was worthy to be consider that in the substantia gelationsa the GABA-ergic nervous structures might form different kinds of autoregulatory synapses by means of which thefunction in spinal cord can. be regulated on a complex basis.