摘要
目的:研究大鼠中缝背核内远位触液神经元与脑实质结构之间的超微结构联系,以探明这种神经元传递信息的方向。方法:用霍乱毒素亚单位B与辣根过氧化物酶复合物(CB-HRP)顺、逆行追踪与电镜技术相结合。结果:中缝背核的触液神经元(以“+”表示)与脑实质的非触液神经元(以“-”表示)之间主要有两种突触形式:轴(-)-树(+)突触和树(-)-树(+)突触,标记的树突多成簇状分布,有的形成树突中心球样的结构,在第三脑室侧壁尚见有被标记的轴突终末伸入脑脊液中。这些突触既有 GrayⅠ型(兴奋型),也有 Gray Ⅱ型(抑制型),但它们的共同特点是突触前成分均为非触液神经元的结构构成,突触后成分均为触液神经元的结构构成。结论:中缝背核的远位触液神经元既可以接受兴奋性信息,也可以接受抑制性信息,并将这些信息自脑实质向脑脊液方向传递。
Objective: To study the ultrastructural relationship between distal neurons contacting cere- brospinal fluid (CSF) in the dorsal raphe nucleus (DR) and neurons no-contacting CSF in the brain parenchyma. Methods: An antergrade and retrograde tracing of the cholera toxin subunit B with horseradish peroxidase (CB-HRP) and electron microscope. Results: There were mainly two synaptic types between neurons contacting CSF in DR and neurons no-contacting CSF in the brain parenchyma: A dendro (-)-dendritic (+) synapse and an axo (-)-dendritic (+) synapse ('-' represents neurons no-contacting CSF and '+' represents neurons contacting CSF). The labelled dendrites by CB-HRP distributed in a cluster, and some of them formed dendritic central complex. The labelled axon terminal by CB-HRP extended into CSF in the cavity of the third ventricle. Both type Gray Ⅰ(exciting ) and Gray Ⅱ(inhibiting) synapses were found and the presynaptic elements were formed by neurons no-contacting CSF and the postsynaptic elements by neu- rons contacting CSF. Conclusion: This paper firstly reported that distal neurons contacting CSF in DR could receive both exciting and inhibiting messengers and transmit them from brain parenchyma to CSF.
出处
《解剖学杂志》
CAS
CSCD
北大核心
1999年第5期388-391,共4页
Chinese Journal of Anatomy
基金
江苏省自然科学基金
关键词
脑脊液
中缝背核
神经元
超声结构
触液神经元
cerebrospinal fluid
neuron contacting cerebrospinal fluid
dorsal raphe nucleus
neuron
rat