Inhibitory control of intracerebellar nuclei by the Purkinje cell axons
Inhibitory control of intracerebellar nuclei by the Purkinje cell axons
复制标题
浦肯野细胞轴突对小脑内核的抑制控制
作者：
Dr. M. Ito;Dr. M. Yoshida;Dr. K. Obata;Dr. N. Kawai;Dr. M. Udo
摘要用细胞内微电极技术研究了麻醉猫小脑核团神经元的突触事件。这些细胞是通过它们沿轴突的逆行激活和/或它们在组织切片中的位置来识别的。在外侧核细胞中，刺激上覆小脑半球外周皮质可单突触地诱发IPSP。在间位核和顶核细胞中，顶叶皮质和顶叶皮质分别产生相似的IPSP。因此，浦肯野细胞对其靶神经元施加抑制作用的假设不仅适用于先前提出的Deiters神经元，也适用于小脑核中的细胞。刺激下橄榄核、桥核和外侧网状核的小脑传入神经，在小脑核细胞产生潜伏期较短的EPSP，可能是通过这些传入神经的轴突侧支实现的。在EPSP之后是IPSP和去抑制性质的缓慢去极化，正如以前在Deiters神经元中所研究的那样，这可能分别是由于浦肯野细胞通过小脑皮质内机制的激活和随后的抑制而引起的。
SummaryIn anaesthetized cats, synaptic events in cerebellar nuclei neurones were investigated with intracellular microelectrode techniques. These cells were identified by their antidromic activation along their axons and/or by their location in histological sections. In the cells of lateral nucleus IPSPs were induced monosynaptically during stimulation of the overlying hemispheral cortex of the cerebellum. In the cells of nuclei interpositus and fastigii, similar IPSPs were produced from the paravermal and vermal cortices, respectively. The postulate that the Purkinje cells exert an inhibitory action upon their target neurones thus applies not only to Deiters neurones, as previously proposed, but also to cells in the cerebellar nuclei. Stimulation of the cerebellar afferents at the inferior olive, the pontine nucleus and the lateral reticular nucleus produced EPSPs in cerebellar nuclei cells with relatively brief latencies, probably through axon collaterals of these afferents. The EPSPs were followed by IPSPs and slow depolarizations of disinhibitory nature, which, as studied previously in Deiters neurones, might be caused respectively by activation and subsequent depression of Purkinje cells through the cerebellar intracortical mechanisms.