Goto Jun-Ichi, Inoue Takafumi, Kuruma Akinori, Mikoshiba Katsuhiko
Division of Molecular Neurobiology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 Japan.
Neurosci Res. 2006 May;55(1):28-33. doi: 10.1016/j.neures.2006.01.001. Epub 2006 Feb 10.
Changes in synaptic efficacy at the parallel fiber (PF)-Purkinje cell (PC) synapse are postulated to be a cellular basis for motor learning. Although long-term efficacy changes lasting more than an hour at this synapse, i.e., long-term potentiation and depression, have been extensively studied, relatively short lasting synaptic efficacy changes, namely short-term potentiation (STP) lasting for tens of minutes, have not been discussed to date. Here we report that this synapse shows an apparent STP reliably by a periodic burst pattern of homosynaptic stimulation. This STP is presynaptically expressed, since it accompanies with a reduced paired-pulse facilitation and is resistant to postsynaptic Ca(2+) reduction by BAPTA injection or in P/Q-type Ca channel knockout cerebella. This novel type of synaptic plasticity at the PF-PC synapse would be a clue for understanding the presynaptic mechanisms of plasticity at this synapse.
平行纤维（PF）-浦肯野细胞（PC）突触处的突触效能变化被认为是运动学习的细胞基础。尽管在此突触处持续超过一小时的长期效能变化，即长时程增强和抑制，已得到广泛研究，但相对短暂的突触效能变化，即持续数十分钟的短时程增强（STP），迄今为止尚未被讨论。在这里我们报告，通过同突触刺激的周期性爆发模式，该突触可靠地表现出明显的STP。这种STP是在突触前表达的，因为它伴随着配对脉冲易化的降低，并且对通过注射BAPTA或在P/Q型钙通道敲除的小脑中降低突触后Ca(2+)具有抗性。PF-PC突触处这种新型的突触可塑性将为理解该突触可塑性的突触前机制提供线索。
