Woodson W, Angaut P
Exp Brain Res. 1984;56(1):167-82. doi: 10.1007/BF00237454.
The distribution, organization and origin of the ipsilateral descending limb of the Brachium Conjunctivum (B.C.), have been studied in the rat by using anterograde and retrograde tracing techniques. After injections of tritiated leucine/proline into the lateral cerebellar nucleus, covering both its medial part, corresponding to the dorsolateral hump (DLH) of Goodman et al. (1963) and its lateral part, (designated here as the lateral dentate, LD), and the neighboring interposed nucleus (NI), emerging fibres are numerous and leave laterally from the B.C. On the contrary, injections restricted to LD reveal very few such fibers. Within the lateral parvocellular reticular formation (LPRF) terminal labelling is heavy, and moderate to sparse within the adjacent trigeminal complex. Rostro-caudally, silver grain accumulation within the LPRF extends from the level of the motor trigeminal nucleus (VM) to the pyramidal decussation, exhibiting a cephalocaudal decrease of grain density. Within the trigeminal complex, labelling occurs in the caudal VM, the dorsal portion of the principal sensory nucleus, and within and around the trigeminal spinalis oralis. In addition, the area surrounding the VM (in part corresponding to the supratrigeminal region of Lorente de Nó 1922, 1933) is moderately labelled. After injections of HRP into various levels of the ipsilateral descending B.C.'s projection field, retrogradely labelled cells are numerous within the DLH. A slightly lesser amount of labelled cells are found in the lateral half of the NI, primarily concerning the nucleus interpositus posterior. Within the LD, only a few labelled cells are observed: these are mainly restricted to the dorsal portion at rostral levels of the nucleus. The results obtained by both the anterograde and retrograde studies suggest an absence of a topographic organization within this descending B.C. component. The possible functional meaning of these results is discussed.
采用顺行和逆行追踪技术，在大鼠中研究了结合臂同侧下行支（B.C.）的分布、组织和起源。向外侧小脑核注射氚标记的亮氨酸/脯氨酸后，覆盖其内侧部分，对应于古德曼等人（1963年）的背外侧隆起（DLH）及其外侧部分（此处称为外侧齿状核，LD）以及相邻的间位核（NI），出现的纤维很多，并从B.C.向外侧离开。相反，局限于LD的注射显示出很少有这样的纤维。在外侧小细胞网状结构（LPRF）内，终末标记很重，在相邻的三叉神经复合体中则为中度至稀疏。在 rostro - caudally方向上，LPRF内的银粒积累从运动三叉神经核（VM）水平延伸至锥体交叉，呈现出颗粒密度的头尾向降低。在三叉神经复合体内，标记出现在尾侧VM、主感觉核的背侧部分以及三叉神经口脊髓束内和周围。此外，VM周围区域（部分对应于洛伦特·德·诺1922年、1933年的三叉上区）有中度标记。向同侧下行B.C.投射野的不同水平注射HRP后，在DLH内逆行标记的细胞很多。在NI的外侧半部分发现的标记细胞数量略少，主要涉及后间位核。在LD内，仅观察到少数标记细胞：这些细胞主要局限于核头侧水平的背侧部分。顺行和逆行研究获得的结果表明，该下行B.C.成分内不存在拓扑组织。讨论了这些结果可能的功能意义。
