Nyberg G
Department of Anatomy, Uppsala University, Sweden.
J Comp Neurol. 1988 May 1;271(1):143-52. doi: 10.1002/cne.902710114.
The projection of forelimb nerves innervating the paw to the cuneate nucleus was studied in the cat by the transganglionic transport method. Exposure of a single digital nerve to the tracer (a conjugate of horseradish peroxidase to wheat-germ agglutinin) resulted in a longitudinal sequence of labeled patches throughout the extent of the nucleus. In the middle region the labeled patches coincided with the location of the cell clusters that are characteristic of this part of the nucleus. A very precise somatotopic termination pattern was found in the middle region of the nucleus. Afferent fibers from the palm were represented superficially close to the dorsal rim. The digits were represented in a mediolateral sequence, with the first digit in the dorsolateral part of the nucleus and the fifth digit in the dorsomedial part. The ventral surfaces of the digits were represented superficial to the dorsal surfaces. The dorsum of the paw was represented close to the center of the nucleus. A similar somatotopic organization, but much less detailed, was found in the rostral and caudal regions of the cuneate nucleus. These dissimilarities in somatotopic detail between the different cytoarchitectonic regions of the cuneate nucleus probably reflect differences in function between these regions.
采用跨神经节运输法，在猫身上研究了支配爪子的前肢神经向楔状核的投射。将示踪剂（辣根过氧化物酶与麦胚凝集素的结合物）注入单根指神经，结果在整个楔状核范围内出现了一系列纵向排列的标记斑。在楔状核中部区域，标记斑与该区域特有的细胞簇位置重合。在楔状核中部区域发现了非常精确的躯体定位终止模式。来自手掌的传入纤维在靠近背侧边缘的浅层区域投射。各手指的传入纤维按内外侧顺序排列，第一指在楔状核的背外侧部分，第五指在背内侧部分。手指的腹侧面投射在背侧面的浅层。爪子的背面投射在楔状核的中心附近。在楔状核的头端和尾端区域也发现了类似的躯体定位组织，但细节程度要低得多。楔状核不同细胞构筑区域在躯体定位细节上的这些差异，可能反映了这些区域之间功能的差异。
