Cortical target depletion and ingrowth of geniculocortical axons: implications for cortical specification.
Cortical target depletion and ingrowth of geniculocortical axons: implications for cortical specification.
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皮质目标耗竭和膝皮质轴突向内生长：对皮质规范的影响。
DOI：
10.1093/cercor/6.3.457
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Finlay,BL
中科院分区：
文献类型：
--
作者：
Woo,TU;Finlay,BL
在新皮质发育的早期，丘脑皮质轴突可能会及时到达，在局部分化的几个方面指导迁移的皮质神经元，如第四层神经元的数量和传出连接。在丘脑皮质侵入之前，第四层神经元迁移到皮质板，这表明这些神经元可能暗示或热带地指导了丘脑的生长。为了探讨第IV层神经元与其丘脑皮质输入的相互作用，我们在胚胎14d对正常纹状皮质产生第IV层神经元的定时妊娠仓鼠给予有丝分裂抑制剂甲氧基甲氧基甲醇醋酸酯(MAM)。皮质神经元的整体数量减少，缺少小直径颗粒神经元，以及缺少密度降低的胼胝体投射神经元，这表明脑室带内IV层细胞的耗竭以及亚板或皮质板中丘脑传入纤维的消失都不影响后来产生的神经元群(可能是II/III层神经元)获得IV层的形态和连接特性。将DIL从胚胎(E15)和出生后(P7)注入动物外侧膝状体背侧核(LGD)，表明丘脑轴突相对于V层的最终位置不受E14神经元缺失的影响。在正常视皮层中，膝状体皮质轴突在P4未分化皮质板正下方的上皮质的假定靶层开始树枝状生长，而在MAM动物中，这一过程发生在1d后。在MAM动物较薄的皮质中，树枝状突起的范围和密度明显减少。因此，我们没有发现丘脑皮质轴突指示迁移的神经元呈现IV层表型的证据；如果指示确实发生，它必须在非常有限的时间窗口发生。在没有这种表型细胞的情况下，丘脑轴突也可以找到它们的板层位置。
During the early development of the neocortex, thalamocortical axons arrive potentially in time to instruct migrating cortical neurons in several aspects of local differentiation, such as number of layer IV neurons and efferent connectivity. Migration of layer IV neurons into the cortical plate just precedes thalamocortical invasion, suggesting that these neurons could cue or tropically direct thalamic ingrowth. To explore the interactions of layer IV neurons and their thalamocortical input, we administered a mitotic inhibitor methylazoxymethanol acetate (MAM) intraperitoneally to timed pregnant hamsters on E14 when layer IV neurons are normally being generated in striate cortex. Reduced numbers of cortical neurons overall, the absence of small-diameter granule neurons, and the absence of the zone of reduced density of callosally projecting neurons suggest that neither the depletion of layer IV cells in the ventricular zone nor thalamic afferents in the subplate or cortical plate respecify the later generated cohort of neurons (presumptive layer II/III neurons) to acquire morphological and connectional properties of layer IV. Dil injections into the dorsal lateral geniculate nucleus (LGd) of animals from embryonic (E15) and postnatal (P7) ages show that the final position of thalamic axons with respect to layer V is not affected by the absence of E14 neurons. In the normal visual cortex, geniculocortical axons have begun their arborization in their presumptive target layer in the upper cortex immediately below the undifferentiated cortical plate on P4, while in MAM animals, this process occurs 1 d later. The extent and density of arborization is much reduced in the thinner cortex of the MAM animals. We thus find no evidence for instruction of migrating neurons by thalamocortical axons to assume the layer IV phenotype; if instruction does occur, it must take place in a very restricted time window. Thalamic axons can also find their laminar position in the absence of cells of this phenotype.
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金黄地鼠大脑皮层细胞增殖、迁移和分化
影响因子：
2.5
作者：
M. Shimada;J. Langman
通讯作者：
J. Langman
DOI：
10.1073/pnas.88.6.2083
发表时间：
1991-03-01
影响因子：
11.1
作者：
RAKIC, P;SUNER, I;WILLIAMS, RW
通讯作者：
WILLIAMS, RW
由金鱼视网膜中的神经毒性破坏定义的外周环的生长速率。
影响因子：
2.9
作者：
K. Negishi;T. Teranishi;S. Kato
通讯作者：
S. Kato
玻璃体内红藻氨酸对鸡视网膜特定细胞类型的剂量依赖性影响
影响因子：
3.3
作者：
C. A. Ingham;I. Morgan
通讯作者：
I. Morgan
辐射损伤后胎儿眼睛的修复。
DOI：
10.1001/archopht.1955.00930020357004
发表时间：
1955
期刊：
A.M.A. archives of ophthalmology
影响因子：
--
作者：
R. Rugh;J. Wolff
通讯作者：
J. Wolff