Bishop G A
Department of Cell Biology, Neurobiology and Anatomy, Ohio State University, Columbus 43210.
Anat Embryol (Berl). 1993 Sep;188(3):287-97. doi: 10.1007/BF00188219.
Basket cell axons terminate directly on the Purkinje cell body in the mammalian cerebellum and thus are in a position to have a direct influence on this neuron. In the present study, individual basket cells were intracellularly filled with horseradish peroxidase and the morphological characteristics and distribution of their axons were analyzed and quantified. The horizontally directed axon of basket cells preferentially distributes toward one side of the cell body, and is usually directed toward the base of the folium. In their course, the axons give rise to three types of axonal specializations including descending collaterals that form the complex endings around the axon hillocks and somata of Purkinje cells (i.e. the pinceau), beaded tendrils that arise from the descending collaterals and distribute to the Purkinje cell and upper granule cell layer, and beaded tendrils that arise directly from the horizontal axon to enter the molecular layer. In some respects, basket cells comprise a heterogeneous population of neurons on the basis of the length of their axon, as well as the number, distribution, and morphological characteristics of the axonal collaterals. The major finding of this study is that a single basket cell does not form a pinceau around the axon hillock of every Purkinje cell located along the course of its horizontal axon. Further, the pinceaux that are formed vary in their complexity. These findings suggest that the classic concept of off-beam inhibition mediated by basket cells is more complex than previously described.
篮状细胞轴突直接终止于哺乳动物小脑的浦肯野细胞体上，因此能够对该神经元产生直接影响。在本研究中，通过细胞内注射辣根过氧化物酶标记单个篮状细胞，并对其轴突的形态特征和分布进行分析和量化。篮状细胞水平方向的轴突优先向细胞体的一侧分布，通常指向小叶的基部。在其行程中，轴突产生三种类型的轴突特化结构，包括下行侧支，其在浦肯野细胞的轴突丘和胞体周围形成复杂终末（即篮状终末）；串珠状卷须，由下行侧支发出并分布到浦肯野细胞和上颗粒细胞层；以及直接从水平轴突发出进入分子层的串珠状卷须。在某些方面，篮状细胞根据其轴突长度以及轴突侧支的数量、分布和形态特征，构成了一个异质性的神经元群体。本研究的主要发现是，单个篮状细胞不会在其水平轴突行程沿线的每个浦肯野细胞的轴突丘周围形成篮状终末。此外，形成的篮状终末在其复杂性上存在差异。这些发现表明，由篮状细胞介导的离束抑制的经典概念比之前描述的更为复杂。
