Elimination and strengthening of glycinergic/GABAergic connections during tonotopic map formation
Elimination and strengthening of glycinergic/GABAergic connections during tonotopic map formation
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DOI：
10.1038/nn1015
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发表时间：
2003-03-01
影响因子：
25
通讯作者：
Kandler, K
中科院分区：
文献类型：
--
作者：
Kim, G;Kandler, K
突触的消除和加强是兴奋性神经元网络发育组织的中心机制。然而，关于这些过程是否也参与建立精确的抑制回路，我们知之甚少。我们研究了听力发作前的大鼠在tonotopically组织，甘氨酸途径的内侧核的斜方体（MNTB）的外侧上级橄榄（LSO），这是哺乳动物的声音定位系统的一部分，功能连接的发展。我们发现LSO神经元在功能上与其初始输入的75%相分离，导致功能地形的两倍锐化。这是伴随着一个12倍的增加所产生的突触电导维持个人的输入。MNTB-LSO突触的功能消除仅限于这些甘氨酸能/GABA能突触兴奋的时期。这些结果提供了新的见解的机制，精确组织的抑制电路在发展过程中建立。
Synapse elimination and strengthening are central mechanisms for the developmental organization of excitatory neuronal networks. Little is known, however, about whether these processes are also involved in establishing precise inhibitory circuits. We examined the development of functional connectivity before hearing onset in rats in the tonotopically organized, glycinergic pathway from the medial nucleus of the trapezoid body (MNTB) to the lateral superior olive (LSO), which is part of the mammalian sound localization system. We found that LSO neurons became functionally disconnected from similar to75% of their initial inputs, resulting in a two-fold sharpening of functional topography. This was accompanied by a 12-fold increase in the synaptic conductance generated by maintained individual inputs. Functional elimination of MNTB-LSO synapses was restricted to the period when these glycinergic/GABAergic synapses are excitatory. These results provide new insights into the mechanisms by which precisely organized inhibitory circuits are established during development.