Sil'kis I G
Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow.
Zh Vyssh Nerv Deiat Im I P Pavlova. 2000 Nov-Dec;50(6):899-912.
The model of simultaneous interrelated modification in the efficacy of synaptic inputs to different neurons of the olivary-cerebellar network is developed. The model is based on the following features of the network: simultaneous activation of the input layer (granule) cells and the output layer (deep cerebellar nuclei) cells by mossy fibers; simultaneous activation of Purkinje cells and cerebellar cells of the input and output layers by climbing fibers and their collaterals; the existence of local feedback excitatory, inhibitory, and disinhibitory circuits. The rise (decrease) of posttetanic Ca2+ concentration in reference to the level produced by previous stimulation causes the decrease (increase) in cGMP-dependent protein kinase G activity, and increase (decrease) inprotein phosphatase 1 activity. Subsequent dephosphorylation (phosphorylation) of ionotropic receptors results in simultaneous LTD (LTP) of the excitatory input together with the LTP (LTD) of the inhibitory input to the same neuron. The character of interrelated modifications of synapses at different cerebellar levels strongly depends on the olivary cell activity. In the presence (absence) of the signal from the inferior olive LTD (LTP) of the output cerebellar signal can be induced.
建立了橄榄小脑网络中不同神经元突触输入效能同时相关修饰的模型。该模型基于该网络的以下特征：苔藓纤维同时激活输入层（颗粒）细胞和输出层（小脑深部核团）细胞；攀缘纤维及其侧支同时激活浦肯野细胞以及输入层和输出层的小脑细胞；存在局部反馈兴奋性、抑制性和去抑制性回路。与先前刺激产生的水平相比，强直后Ca2+浓度的升高（降低）导致cGMP依赖性蛋白激酶G活性降低（升高），蛋白磷酸酶1活性升高（降低）。随后离子型受体的去磷酸化（磷酸化）导致同一神经元兴奋性输入的同时长时程抑制（LTP）以及抑制性输入的LTP（长时程抑制）。不同小脑水平突触相关修饰的特征强烈依赖于橄榄细胞的活动。在存在（不存在）来自下橄榄核的信号时，可以诱导小脑输出信号的长时程抑制（LTP）。
