Matsushita M
Department of Anatomy, Institute of Basic Medical Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan.
J Comp Neurol. 1999 Oct 4;412(4):633-48. doi: 10.1002/(sici)1096-9861(19991004)412:4<633::aid-cne5>3.0.co;2-q.
The spinocerebellar tracts arising from the upper lumbar cord consist of the dorsal and the ventral spinocerebellar tracts (DSCT and VSCT), which ascend ipsilaterally and contralaterally, respectively. By using anterograde labeling with biotinylated dextran in the rat, this study examined whether the lumbar DSCT and the VSCT project to the cerebellar nuclei. Injections of the tracer were made unilaterally at levels between the L1 and L3 segments, with diffusion to either a rostral or a caudal segment. The injections resulted in bilateral labeling of axon terminals in the cerebellar nuclei. In the medial nucleus, labeled terminals were distributed in medial, ventral, and ventrolateral parts of the middle subdivision and ventral parts of the caudomedial subdivision. In the anterior interpositus nucleus, they were distributed in medial and dorsomedial parts throughout the rostrocaudal extent. Labeled terminals were seen within the dorsomedial crest region. In the posterior interpositus nucleus, labeled terminals were seen in the rostromedial extension, the caudomedial part, and the caudal pole. Labeled terminals were seen in the hilus and the ventral part of the lateral nucleus. Projections of the DSCT and the VSCT to these regions were confirmed after tracer injections preceded by sectioning of either tract. Both tracts projected bilaterally, but the DSCT projected mainly ipsilaterally. The present study suggests that the spinocerebellar tracts originating from the upper lumbar cord (the lumbar DSCT and the VSCT) project to specific areas of the cerebellar nuclei to transmit information about the peripheral and central events during the movement of hindlimbs.
发自腰髓上部的脊髓小脑束由背侧和腹侧脊髓小脑束（DSCT和VSCT）组成，它们分别同侧和对侧上行。本研究通过在大鼠中使用生物素化葡聚糖进行顺行标记，来检测腰段DSCT和VSCT是否投射至小脑核。示踪剂单侧注射于L1和L3节段之间的水平，并扩散至头侧或尾侧节段。注射导致小脑核内轴突终末的双侧标记。在内侧核中，标记终末分布于中间亚核的内侧、腹侧和腹外侧部分以及尾内侧亚核的腹侧部分。在前间位核中，它们分布于整个头尾范围内的内侧和背内侧部分。在背内侧嵴区域可见标记终末。在后间位核中，在嘴内侧延伸部、尾内侧部分和尾极可见标记终末。在外侧核的门部和腹侧部分可见标记终末。在切断任一脊髓小脑束后进行示踪剂注射，证实了DSCT和VSCT向这些区域的投射。两条束均双侧投射，但DSCT主要同侧投射。本研究提示，发自腰髓上部的脊髓小脑束（腰段DSCT和VSCT）投射至小脑核的特定区域，以传递后肢运动过程中外周和中枢事件的信息。
