Remodelling of early axonal projections through the selective elimination of neurons and long axon collaterals.
Remodelling of early axonal projections through the selective elimination of neurons and long axon collaterals.
复制标题
通过选择性消除神经元和长轴突侧支来重塑早期轴突投射。
DOI：
10.1002/9780470513422.ch8
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
O'Leary,DD
中科院分区：
文献类型：
--
作者：
O'Leary,DD
使用神经解剖学技术的研究表明，成熟脊椎动物大脑的连接特征是由发育期间最初建立的投射的相当大的改进所带来的。神经元和长轴突侧支的选择性损失在这种重塑过程中起着重要作用，如大鼠视网膜和皮质的发育所示。在视网膜中，三分之二的神经节细胞（RGC）早期死亡。这种损失用于选择性地去除做出错误轴突投射的RGC，包括投射到不正确靶点、正确靶点的不适当部分或脑的错误侧的RGC。使用钠通道阻滞剂河豚毒素的研究表明，在大鼠中，选择性消除错误投射的RGCs部分基于冲动活动的模式。在皮层中，说明了一种不同的机制。所有新皮质区最初产生胼胝体和锥体束轴突，但通过选择性侧支消除过程，不涉及细胞死亡，这些预测假设在成年大鼠中看到的有限分布。操作导致维持这样长的侧支表明，它们的去除是功能和局部决定的。与消除错误相反，这种消除侧支的现象可能是一种发展策略，用于产生连接多样性，同时限制皮层区域规范所需的信息量。
Studies using neuroanatomical techniques have shown that the connections characteristic of the mature vertebrate brain are brought about by a considerable refinement of the projections initially established during development. The selective loss of neurons and long axon collaterals plays a major role in this remodelling process as illustrated in the development of the retina and cortex of the rat. In the retina, two‐thirds of the initial population of ganglion cells (RGCs) die early. This loss serves to remove selectively RGCs that make erroneous axonal projections, including those which project to an incorrect target, to an inappropriate part of a correct target, or to the wrong side of the brain. Studies using the sodium channel blocker, tetrodotoxin, suggest that in rats the selective elimination of erroneously projecting RGCs is based, in part, on patterns of impulse activity. In the cortex a different mechanism is illustrated. All neocortical areas initially give rise to callosal and pyramidal tract axons but through a process of selective collateral elimination not involving cell death these projections assume the limited distributions seen in adult rats. Manipulations resulting in the maintenance of such long collaterals suggest that their removal is functionally and locally determined. In contrast to error elimination, this phenomenon of collateral elimination may be a developmental strategy for generating connectional diversity while limiting the amount of information required for the regional specification of the cortex.
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影响因子：
56.9
作者：
R. Meyer
通讯作者：
R. Meyer
在产后早期发育过程中，大鼠视神经轴突丢失。
影响因子：
2.9
作者：
K. Lam;A. Sefton;Max R. Bennett
通讯作者：
Max R. Bennett
DOI：
10.1007/bf01181746
发表时间：
1981-01-01
期刊：
JOURNAL OF NEUROCYTOLOGY
影响因子：
--
作者：
BIXBY, JL
通讯作者：
BIXBY, JL
波士顿暹罗猫与普通猫视觉系统半球间连接的解剖
DOI：
--
发表时间：
1977
期刊：
The Journal of comparative neurology
影响因子：
--
作者：
C. Shatz
通讯作者：
C. Shatz
正常神经系统发育中的偶然性、重复性和错误
影响因子：
1
作者：
P. Clarke
通讯作者：
P. Clarke