Homosynaptic long-term synaptic Potentiation of the "Winner" climbing fiber synapse in developing Purkinje cells
Homosynaptic long-term synaptic Potentiation of the "Winner" climbing fiber synapse in developing Purkinje cells
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DOI：
10.1523/jneurosci.4074-07.2008
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发表时间：
2008-01-23
影响因子：
5.3
通讯作者：
Konnerth, Arthur
中科院分区：
文献类型：
--
作者：
Bosman, Laurens W. J.;Takechi, Hajime;Konnerth, Arthur
在神经元回路的发育形成过程中，多余的突触被消除，而持续存在的突触被加强。在未成熟的小脑中，攀缘纤维-浦肯野细胞突触经历了明显的突触重新布线，从出生时的多神经支配到成年时的单神经支配。这一过程的早期阶段包括最初同样强的突触分化为一个“大”和几个“小”突触输入。通过对大鼠小脑片浦肯野细胞进行全细胞记录，我们发现浦肯野细胞及其传入攀爬纤维的同时激活可诱导同突触长时程突触增强（LTP）。这种LTP需要突触后Ca 2+信号传导，并涉及突触后AMPA受体的单通道电导的增加。有趣的是，LTP只发生在大的突触输入。在最终被消除的小输入处没有观察到。因此，我们确定了一种新的形式的LTP，表达独特，只是在一个有限的时期的早期发展中的大型攀登纤维的投入。我们的研究结果表明，这种LTP介导的活动依赖性成熟的“赢家”攀爬纤维。
During the developmental formation of neuronal circuits, redundant synapses are eliminated and persisting synapses strengthened. In the immature cerebellum, climbing fiber-Purkinje cell synapses undergo a pronounced synaptic rewiring, from a multiple innervation around birth to a mono-innervation in adults. An early stage of this process consists in the differentiation of initially equally strong synapses into one "large" and several "small" synaptic inputs. By performing whole-cell recordings in Purkinje cells of rat cerebellar slices, we found that the coincident activation of a Purkinje cell and one of its afferent climbing fibers induces homosynaptic long-term synaptic potentiation (LTP). This LTP requires postsynaptic Ca2+ signaling and involves an increase in the single channel conductance of the postsynaptic AMPA receptors. Interestingly, LTP occurs exclusively at large synaptic inputs. It is not observed at small inputs that are eventually eliminated. Thus, we identified a new form of LTP that is expressed uniquely and just for a restricted period of early development in the large climbing fiber inputs. Our results suggest that this LTP mediates the activity-dependent maturation of the "winner" climbing fiber.