Light microscopic observations on the morphology of sympathetic preganglionic neurons in the pigeon, Columba livia.
Light microscopic observations on the morphology of sympathetic preganglionic neurons in the pigeon, Columba livia.
复制标题
鸽子交感神经节前神经元形态的光显微镜观察。
DOI：
10.1016/0306-4522(87)90105-9
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发表时间：
1987
期刊：
影响因子：
3.3
通讯作者：
Bogan,N
中科院分区：
文献类型：
--
作者：
Cabot,JB;Bogan,N
实验在麻醉、固定、人工呼吸的鸽子(Columba Livia)身上进行。获得了56个反向激活和碰撞的交感节前神经元的细胞外记录。用辣根过氧化物酶对11个细胞进行细胞内标记，并在光镜下重建。在电生理学方面，标记神经元和未标记神经元之间没有统计学差异。观察到四种不同的体型：纺锤形、梨形、多极和星形。11个细胞中有9个位于节前主细胞柱(Terni柱)内，另外2个位于棘间核内。主柱神经元表现为平面的水平排列的树突，其主要伸展方向为吻尾。出乎意料的是，这些细胞中的大多数也有树突分支投射，横跨同侧中间带的整个宽度。对侧树突状终末分支在7个神经元中明显。中间带神经元呈多极形，其树突排列方式与主柱节前细胞明显不同。间质细胞的树突在脊髓横轴内斜行，主要树突伸入背角的底部、背外侧索和腹角的背侧。无论体细胞亚核的位置如何，节前树突的形态都是相似的：(1)一级、二级和三级突起基本光滑。(2)近端和远端细小的突起呈串珠状或“曲张”状。(3)远端突起形成细茎、棘状附属物。节前神经元的轴突既有胞体，也有初级和次级树突。两个细胞的轴突在椎管内分叉。本研究结果详细描述了中间核内节前神经元的体细胞结构和伴随的树突。这些观察还包括显示交感神经节前轴突在椎管内侧支的解剖学证据。一般来说，位于主细胞柱内的鸟类交感节前神经元似乎在结构上与它们在胸髓中外侧细胞柱内的哺乳动物神经元同源。
Experiments were performed in anesthetized, immobilized, artificially respirated pigeons (Columba livia). Extracellular recordings from 56 antidromically activated and collided sympathetic preganglionic neurons were obtained. Eleven cells were intracellularly labeled with horseradish peroxidase and reconstructed at the light microscopic level. Electrophysiologically there were no statistical differences between labeled and unlabeled neurons. Four different somatic shapes were observed: fusiform, pyriform, multipolar and stellate. Nine of 11 cells were located within the principal preganglionic cell column (column of Terni), the other two were within nucleus intercalatus spinalis. Principal column neurons exhibited planar, horizontally aligned dendritic arbors with major extensions directed rostrocaudally. Unexpectedly, the majority of these cells also had dendritic branch projections which spanned the entire width of the ipsilateral zona intermedia. Contralateral dendritic terminal arborizations were evident in seven neurons. Intercalatus neurons were multipolar-shaped and exhibited a notably different dendritic arrangement from principal column preganglionic cells. The dendrites of intercalated cells coursed obliquely within the transverse spinal cord axis, giving rise to major dendritic extensions into the base of the dorsal horn, the dorsolateral funiculus and the dorsal aspects of the ventral horn. Irrespective of somatic subnuclear location, the morphology of preganglionic dendrites was similar:(1)Largely primary, secondary and tertiary processes were smooth.(2)Fine caliber proximal and distal elements appeared beaded or “varicose.”(3)Distal processes gave rise to thin-stalked, spine-like appendages. The axons of preganglionic neurons arose from cell bodies as well as primary and secondary dendrites. The axons of two cells branched intraspinally.The present findings provide detailed descriptions of the somatic structures and accompanying dendritic trees of preganglionic neurons within nucleus intercalatus. The observations also include anatomical evidence showing the intraspinal collateralization of sympathetic preganglionic axons. In general, avian sympathetic preganglionic neurons located within the principal cell column appear to be structurally homologous to their mammalian counterparts within the intermediolateral cell column of thoracic spinal cord.