包埋前免疫电镜双标技术在神经解剖学研究中的应用

目的　在超微结构水平观察两种神经递质在纤维终末内的共存或一种神经递质与其相应受体之间的关系。　方法　包埋前免疫电镜双重标记技术———酶标法和免疫金 银标记法相结合的方法。　结果　在免疫反应双重标记的纹状体切片上 ,电镜下观察到大量的SP样 (过氧化物酶免疫反应产物 )阳性终末和SP受体 (SPR ,免疫金 银标记颗粒 )样阳性神经元的胞体和树突 ,同时可见部分SP样阳性轴突终末分别与SPR样阳性神经元的胞体或树突形成对称性轴 体或轴 树突触联系。而在三叉神经脊束核尾侧亚核切片上 ,电镜下可观察到大量的两种囊泡膜谷氨酸转运体 ,即DNPI样 (过氧化物酶免疫反应产物 )和VGluT1样 (免疫金 银标记颗粒 )阳性轴突终末 ,同时还观察到DNPI样和VGluT1样双标的轴突终末与阴性树突形成非对称性突触。　结论　包埋前免疫电镜双重标记技术敏感性较高 ,组织的抗原性保存好 ,特别是在神经解剖学研究中 ,用于研究两种神经递质在同一个细胞或终末内的共存或分析神经递质与其相应受体之间的联系中有独到之处。

THE APPLICATION OF PRE-EMBEDDING DOUBLE-LABELED IMMUNO-ELECTRON MICROSCOPIC METHOD IN THE NEUROANATOMICAL STUDIES

Objective The co existence of two kinds of neurotransmitters in the cell bodies or axon terminals and the relationship between a neurotransmitter and its relevant receptor were observed at the ultrastructural level. Methods The pre embedding double labeled immuno electron microscopic techniques were used by peroxidase immunohistochemistry combined with immunogold silver labeled method. Results In the sections of the striatum,a large number of the SP like immunoreactive(|LI) axon terminals(immunoperoxidase reaction products)and SP receptor(SPR)|LI neuronal cell bodies and dendrites(immunoglold silver grains)were seen in the present study.Some SP|LI axon terminals were observed to form symmetric axon somatic or axon dendritic synaptic contacts with SPR|LI neuronal cell bodies and dendritic profiles.On the other hand,in the sections of caudal spinal trigeminal nucleus,a substantial number of axon terminals of the two kinds of the vesicular glutamate transporters,the differentiation associated Na dependent inorganic phosphate cotransporter(DNPI)and vesicular glutamate transporter of type1(VGluT1),were labeled by peroxidase immunohistochemistry and immunogold silver grains.Some axon terminals were labeled by both DNPI and VGLuT1 immunoreaction formed asymmetric synaptic contact with non labeled dendrite profile.Conclusion The pre embedding double labeled immuno electron microscopic technique has the advantage of higher sensitivity and greater preservation of the antigen in the many tissues.Thus,the present study favors the application of this technique to study the co existence of two kinds of the neurotransmitters in the cell bodies or axon terminals and analyse the relationship between a neurotransmitter and its relevant receptor in the field of the neuroanatomy.