Ito M
Acta Morphol Hung. 1983;31(1-3):213-8.
The learning machine model of the cerebellum by Marr and Albus contains a special type of synaptic plasticity. Experimental evidence for this synaptic plasticity has been meager, but very recently positive evidence has become available. Ito, Sakurai and Tongroach (7) demonstrated the occurrence of a long-lasting depression in mossy fiber responsiveness of Purkinje cells subsequent to conjuctive stimulation of mossy fibers and climbing fibers. A similar long-lasting depression was shown to occurred in sensitivity of Purkinje cell dendrites to a putative neurotransmitter of parallel fibers, i.e., glutamate. Furthermore, Ito and Kano (6) produced a long-lasting depression in the molecular layer of the cerebellar cortex by simultaneous direct stimulation of parallel fibers and climbing fibers. These long-lasting depressions appear to represent a synaptic plasticity of the form proposed by Albus.
马尔和阿尔布斯提出的小脑学习机模型包含一种特殊类型的突触可塑性。关于这种突触可塑性的实验证据一直很少，但最近有了确凿的证据。伊藤、樱井和汤罗奇（7）证明，在苔藓纤维和攀缘纤维联合刺激后，浦肯野细胞的苔藓纤维反应性会出现持久的抑制。类似的持久抑制也出现在浦肯野细胞树突对平行纤维假定神经递质（即谷氨酸）的敏感性上。此外，伊藤和卡诺（6）通过同时直接刺激平行纤维和攀缘纤维，在小脑皮质分子层产生了持久的抑制。这些持久的抑制似乎代表了阿尔布斯提出的那种形式的突触可塑性。
