Compartmental organization and integration of inputs in the cerebellar nuclei

小脑与各种运动的控制有关，具有精确的功能区室化，我们的前期研究发现，小脑皮层的醛缩酶C表达模式与其功能区室化密切相关。浦肯野细胞轴突是小脑皮质的输出，投射到小脑核。与小脑皮质相比，小脑核的神经元输入、输出回路和功能区室化的研究较少。在小脑核中，醛缩酶C表达于浦肯野细胞轴突终末。因此，我首先在三维空间中重建了大鼠小脑核中的醛缩酶C阳性和阴性区域。这表明，醛缩酶C-阴性和阳性区域分别收集在rostrodoral，caudoventral和外侧部分的小脑nucleus.To与这些地区的橄榄投射，我映射的核侧支终止橄榄小脑轴突在三维空间中的大鼠。这揭示了非常精确的地形在核投影橄榄轴突。根据地形图，小脑皮质的功能区室化几乎完全保留在小脑核中。这支持了我们关于醛缩酶C区室化的功能意义的假设，并表明小脑核的吻背侧部（醛缩酶C阴性）可能与躯体感觉相关的功能和小脑核的尾腹侧部和外侧部有关（醛缩酶C阳性）与其他功能有关。此外，标记的浦肯野细胞投射表明，下橄榄和小脑皮质与核团之间一般形成闭环回路。因此，精确的划分和整合的神经元输入在小脑核被揭示。

The cerebellum is concerned with the control of various kinds of movements, suggesting precise functional compartmentalization in it. Our previous studies revealed that the aldolase C expression pattern in the cerebellar cortex is tightly related with its functional compartmentalization. Purkinje cell axons, which are the output of the cerebellar cortex, project to the cerebellar nuclei. Compared to the cerebellar cortex, the cerebellar nuclei have not been much studied in terms of the input and output neuronal circuits and the functional compartmentalization.In the cerebellar nuclei, aldolase C is expressed in the terminals of Purkinje cell axons. Therefore, I first reconstructed aldolase C-positive and negative areas in the cerebellar nuclei in the three-dimensional space in the rat. This revealed that the aldolase C-negative and positive areas are each collected in the rostrodorsal, and caudoventral and lateral parts of the cerebellar nuclei.To relate these areas to the olivary projection, I mapped the nuclear collateral terminations of olivocerebellar axons in three-dimensional space in the rat. This revealed very precise topography in the nuclear projection olivary axons. Based on the topography, the functional compartmentalization in the cerebellar cortex is preserved nearly exactly in the cerebellar nuclei. This supported our hypothesis about the functional significance of aldolase C compartmentalization, and suggests that the rostrodorsal part of the cerebellar nuclei (aldolase C-negative) may be concerned with somatosensory-related functions and the caudoventral and lateral part of the cerebellar nuclei (aldolase C-positive) are concerned with other functions.Furthermore, labeled Purkinje cells projections indicated that the closed-loop circuit between the inferior olive and cerebellar cortex and nuclei was generally formed. Thus, precise compartmentalization and integration of neuronal inputs in the cerebellar nuclei were revealed.