Light microscopic observations on the relationships between 5-hydroxytryptamine-immunoreactive axons and dorsal spinocerebellar tract cells in Clarke's column in the cat.
Light microscopic observations on the relationships between 5-hydroxytryptamine-immunoreactive axons and dorsal spinocerebellar tract cells in Clarke's column in the cat.
复制标题
光显微镜观察猫克拉克柱中 5-羟色胺免疫反应性轴突与背侧脊髓小脑束细胞之间的关系。
DOI：
10.1007/s002219900222
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Fyffe,RE
中科院分区：
文献类型：
--
作者：
Pearson,JC;Sedivec,MJ;Dewey,DE;Fyffe,RE
5-羟色胺（5-HT）对运动神经元、中间神经元和上行束细胞的兴奋性具有多种作用。脊髓小脑束细胞在背角接受突触连接从肾上腺素能轴突，但很少有人知道肾上腺素能轴突和背侧脊髓小脑束（DSCT）细胞在Clarke的柱之间的关系。我们研究了这些关系，通过使用5-HT-免疫反应终扣的免疫组织化学定位和细胞内染色与辣根过氧化物酶（HRP）或神经生物素识别的DSCT细胞在体内的组合。在成年猫，克拉克柱显示出较低的5-HT-免疫反应阳性轴突和终扣比相邻区域的脊髓灰质密度。用光学显微镜分析了11个细胞内染色的DSCT细胞，其中6个细胞在三维空间中完全重建。在标记的DSCT细胞上共观察到3，739个紧密贴壁（每个突触后神经元340±101个：平均值±SD）。大部分（97%）沉积物形成于树突上，包括近端和远端分支，平均密度约为每1，000 µ m2树突膜1.4个沉积物。这些结果表明，球脊髓肾上腺素能系统提供了直接的神经支配的Clarke的柱-DSCT细胞在上腰脊髓和输入广泛分布在所有区域的靶神经元的胞体-树突状细胞膜。
Serotonin (5-HT) exerts a variety of effects on the excitability of motoneurons, interneurons, and ascending tract cells. Spinocerebellar-tract cells in the dorsal horn receive synaptic connections from serotoninergic axons, but little is known about the relationships between serotoninergic axons and dorsal spinocerebellar tract (DSCT) cells in Clarke's column. We studied these relationships by using a combination of immunohistochemical localization of 5-HT-immunoreactive boutons and intracellular staining with horseradish peroxidase (HRP) or neurobiotin of identified DSCT cells in vivo. In the adult cat, Clarke's column displayed a lower density of 5-HT-immunoreactive axons and boutons than adjacent regions of the spinal gray matter. Eleven intracellularly stained DSCT cells were analyzed with light microscopy, and six of these cells were entirely reconstructed in three dimensions. A total of 3,739 close appositions (340±101 per postsynaptic neuron: mean±SD) were observed on the labeled DSCT cells. The majority (97%) of the appositions were formed on dendrites, including proximal and distal branches, with an average density of about 1.4 appositions per 1,000 µm2of dendritic membrane. These results indicate that the bulbo-spinal serotoninergic system(s) provide direct innervation of Clarke's column-DSCT cells in the upper lumbar spinal cord and that the inputs are spread widely over all regions of the target neurons' soma-dendritic membrane.