Buisseret-Delmas C, Angaut P
Laboratoire de Physiologie de la Motricité, URA-385 CNRS, Université Pierre-et-Marie-Curie, Paris, France.
Neurosci Res. 1989 Nov;7(2):131-43. doi: 10.1016/0168-0102(89)90053-9.
The organization of olivary afferents and nuclear efferents of the D-zone of the rat cerebellum was studied by means of tracing with wheat-germ agglutinin-coupled peroxidase using tetramethylbenzidine as a chromagen. The tracer was injected iontophoretically within the cerebellar cortex. This allowed us to study both afferent and efferent pathways of the cerebellar lobules concerned with retrograde and anterograde tracing, respectively. Retrograde cellular labelling in the inferior olive was restricted to the principal olive (PO). Anterograde terminal labelling was found only within the various subdivisions of the nucleus lateralis or dentatus (ND). For any one of our small cortical injections there was a corresponding sagittal band of retrogradely labelled cells in the contralateral PO, and a sagittal band of terminal labelling through the ND. Based on both their olivary and nuclear connections, 3 sagittal subzones can be distinguished within the D-zone of the rat. From medial to lateral, we call them D0, D1 and D2. The 3 subzones run through part of the anterior and posterior lobes. D1 and D2 run continuously from their rostral to their caudal extents whereas D0 is discontinuous. It is interrupted through lobule VIc (crus I). The olivary projections to D0 arise within the medial half of the ventral lamella of the PO, including the dorsomedial cell column. Those to D1 arise within the dorsal lamella of the PO. Those to D2 arise within the lateral half of the ventral lamella of the PO. Rostrocaudally, widely distant cells of the same subdivision of the PO project to the same cerebellar lobule. This indicates extensive convergence of the olivary afferents within each of the 3 hemispheric compartments, D0, D1 and D2. Each of the 3 hemispheric subzones specifically projects to one of the 3 subdivisions distinguished within the ND of the rat, without apparent mediolateral overlapping. The medialmost D0 projects onto the dorsolateral hump; D1 projects more laterally onto the main, magnocellular part of the ND, and D2 projects ventrally onto the parvicellular subdivision of the ND. Thus the sagittal partition of the hemispheric cortex is reflected at the nuclear level. In contrast, Purkinje cell axons from individual lobules appear to branch extensively in the rostrocaudal direction. Therefore, within each of the 3 compartments D0, D1 as well as D2, the nuclear projection of the anterior lobe and the posterior lobe are largely coextensive.
采用小麦胚芽凝集素偶联过氧化物酶（以四甲基联苯胺作为显色剂）进行追踪的方法，研究了大鼠小脑D区橄榄传入纤维和核传出纤维的组织学结构。将示踪剂通过离子电渗法注入小脑皮质内。这使我们能够分别利用逆行追踪和顺行追踪来研究相关小脑小叶的传入和传出通路。下橄榄核中的逆行细胞标记仅限于主橄榄核（PO）。顺行终末标记仅见于外侧核或齿状核（ND）的各个亚区。对于我们的任何一次小范围皮质注射，在对侧PO中都有一条相应的逆行标记细胞的矢状带，以及一条穿过ND的终末标记矢状带。根据其橄榄核和核连接情况，可在大鼠D区内区分出3个矢状亚区。从内侧到外侧，我们将它们称为D0、D1和D2。这3个亚区贯穿前叶和后叶的一部分。D1和D2从其头端到尾端连续分布，而D0是不连续的。它在小叶VIc（小脑脚I）处中断。投射到D0的橄榄核纤维起源于PO腹侧薄片的内侧半部分，包括背内侧细胞柱。投射到D1的纤维起源于PO的背侧薄片。投射到D2的纤维起源于PO腹侧薄片的外侧半部分。在头尾方向上，PO同一亚区中相距很远的细胞投射到同一个小脑小叶。这表明在3个半球区室D0、D1和D2中的每一个区内，橄榄核传入纤维都有广泛的汇聚。3个半球亚区中的每一个都特异性地投射到大鼠ND内区分出的3个亚区之一，没有明显的内外侧重叠。最内侧的D0投射到背外侧隆起；D1更外侧地投射到ND的主要大细胞部分，D2腹侧投射到ND的小细胞亚区。因此，半球皮质的矢状分区在核水平上得到了反映。相比之下，来自单个小叶的浦肯野细胞轴突似乎在头尾方向上广泛分支。因此，在3个区室D0、D1以及D2中的每一个区内，前叶和后叶的核投射在很大程度上是共同延伸的。
