Blatt G J, Eisenman L M
Department of Anatomy, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 19107.
J Comp Neurol. 1988 Jan 22;267(4):603-15. doi: 10.1002/cne.902670412.
The organization of the olivocerebellar projection in the homozygous reeler mouse (rl/rl) was studied with the use of microinjections of 3H-leucine in different regions of the inferior olivary complex (IO) or horseradish peroxidase conjugated with wheat germ agglutinin (WGA-HRP) into medial, intermediate, or lateral regions of the reeler cerebellum. The purpose of this investigation was to determine the pattern of termination of olivocerebellar climbing fibers (CFs) in the cerebellum via an anterograde tracing technique, and to determine the topographic organization of the olivocerebellar projection via both anterograde and retrograde methods. The inferior olive injections were made via the ventral (i.e., retropharygeal) approach to the IO to minimize diffusion into other brainstem precerebellar nuclei and thus to ensure accurate well-restricted, injection sites. Labeled CF terminals were seen in both the superficial Purkinje cell (PC) layer (normally positioned PCs) and around PCs in the granular layer and central masses (ectopic PCs). The pattern of labeling is suggestive of orthogonal organization, in that vertical columns of cells are labeled. This is especially apparent in the medial PC group, where at least three bands are identified. Within an orthogonal band, CF terminals are seen around both superficial and deep Purkinje cells. Our data indicate that olivocerebellar topography is generally similar in reeler and normal mice despite severe abnormalities in target cell position in the reeler. The medial cerebellar region receives input from the caudal two-fifths of the medial accessory olive (MAO). The intermediate PC cluster receives input from more rostral portions of all three olivary divisions (MAO, principal olive [PO] and dorsal accessory olive [DAO] ), while rostral portions of MAO and PO project to the lateral cerebellum. These results indicate that the zonal organization of the olivocerebellar projection in the adult reeler exhibits a pattern generally similar to that seen in normal mice. This suggests that an afferent system can develop a normal organization despite having ectopic targets.
利用向纯合子reeler小鼠（rl/rl）下橄榄复合体（IO）不同区域微量注射³H-亮氨酸，或将与小麦胚凝集素结合的辣根过氧化物酶（WGA-HRP）注入reeler小鼠小脑的内侧、中间或外侧区域，对橄榄小脑投射的组织进行了研究。本研究的目的是通过顺行追踪技术确定橄榄小脑攀缘纤维（CFs）在小脑中的终末模式，并通过顺行和逆行方法确定橄榄小脑投射的拓扑组织。通过腹侧（即咽后）途径向IO注射，以尽量减少扩散到其他脑干小脑前核，从而确保准确、局限良好的注射部位。在浅层浦肯野细胞（PC）层（正常位置的PCs）以及颗粒层和中央团块中的PCs周围（异位PCs）均可见到标记的CF终末。标记模式提示为正交组织，即细胞的垂直柱被标记。这在中间PC组中尤为明显，其中至少可识别出三条带。在一个正交带内，浅层和深层浦肯野细胞周围均可见到CF终末。我们的数据表明，尽管reeler小鼠的靶细胞位置存在严重异常，但reeler小鼠和正常小鼠的橄榄小脑拓扑结构总体相似。小脑内侧区域接受来自内侧副橄榄核（MAO）尾侧五分之二的输入。中间PC簇接受来自所有三个橄榄核亚群（MAO、主橄榄核[PO]和背侧副橄榄核[DAO]）更靠前部分的输入，而MAO和PO的靠前部分投射到小脑外侧。这些结果表明，成年reeler小鼠橄榄小脑投射的分区组织呈现出与正常小鼠总体相似的模式。这表明传入系统尽管有异位靶标，但仍可形成正常组织。
