Quantitative analysis of synaptic distribution along thalamocortical axons in adult mouse barrels
Quantitative analysis of synaptic distribution along thalamocortical axons in adult mouse barrels
复制标题
成年小鼠桶状丘脑皮质轴突突触分布的定量分析
DOI：
10.1002/cne.20300
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发表时间：
2004
影响因子：
2.5
通讯作者：
D. Lev
中科院分区：
文献类型：
--
作者：
E. White;E. Weinfeld;D. Lev
成年小鼠丘脑皮质突触的定量数据主要是通过病变诱导变性标记丘脑传入事件获得的。当退化的轴突可以用电子显微镜识别时，它们已经分裂成许多独立的片段，因此不可能评估沿传入神经完整长度的突触分布。在这里，通过向同侧丘脑注射生物素化右旋糖酐胺来检查轴突的完整长度，从而纠正了这一缺陷。对连续的薄片重建进行分析，以确定树突棘与轴形成的每轴突长度的突触数量以及突触的位置与轴突变异有关。6只小鼠7个轴突节段的平均突触数为0.2个/μm；80%为棘状，20%为枝晶轴状。超过三分之二的轴突变异形成一个突触；其余的大多数形成两个，很少形成三个，而8%的人没有形成一个。虽然大多数突触发生在曲度（88%），但超过12%的突触发生在重建轴突节段的圆柱形区域。这些结果作为使用光学显微镜来量化突触的警告，其中通常的方法是将一个静脉曲张等同于一个突触。对于鼠脑桶的丘脑皮层传入，将一个静脉曲张等同于一个突触的情况在超过30%的情况下是不正确的，并且会排除在丘脑皮层传入的圆柱形区域产生的大约12%的突触连接。[j] .中华神经医学杂志，2004。©2004 Wiley‐Liss, Inc。
Quantitative data on thalamocortical synapses in adult mouse barrels have been obtained largely by using lesion‐nduced degeneration to label thalamic afferents. By the time degenerating axons can be identified with the electron microscope, they have broken up into many separate pieces, making it impossible to assess the distribution of synapses along unbroken lengths of afferent. Here, this deficiency is rectified by examining intact lengths of axon labeled by the injection of biotinylated dextran amine into ipsilateral thalamus. Serial thin section reconstructions were analyzed to determine the numbers of synapses per axon length made with dendritic spines vs. shafts and the locations of synapses with respect to axonal varicosities. Results for seven axonal segments from six mice showed an average of 0.2 synapses/μm; 80% were made with spines and 20% with dendritic shafts. Just over two‐thirds of axonal varicosities formed one synapse; most of the remainder formed two and rarely three, whereas 8% formed none. Although most synapses occurred at varicosities (88%), more than 12% were made at cylindrically shaped regions of the reconstructed axonal segments. These results serve as a caveat for the use of light microscopy to quantify synapses, wherein the usual approach is to equate one varicosity with one synapse. For thalamocortical afferents to mouse barrels, equating one varicosity with one synapse would prove to be incorrect more than 30% of the time and would exclude the roughly 12% of synaptic connections made at cylindrical regions of thalamocortical afferents. J. Comp. Neurol. 479:56–69, 2004. © 2004 Wiley‐Liss, Inc.
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影响因子：
0.9
作者：
LU, SM;LIN, RCS
通讯作者：
LIN, RCS
影响因子：
2.5
作者：
Pinto, DJ;Brumberg, JC;Simons, DJ
通讯作者：
Simons, DJ
神经元网络分析：轴突投影标记技术综述。
DOI：
10.1002/jemt.1060150403
发表时间：
1990
期刊：
Journal of electron microscopy technique
影响因子：
--
作者：
Ralston3rd,HJ
通讯作者：
Ralston3rd,HJ
小鼠“晶须”丘脑的出生后发育：腹后内侧核（VPM）、桶状体及其丘脑皮质中继神经元。
DOI：
10.3109/08990229609052585
发表时间：
1996
期刊：
Somatosensory & motor research.
影响因子：
--
作者：
Zantua,JB;Wasserstrom,SP;Arends,JJ;Jacquin,MF;Woolsey,TA
通讯作者：
Woolsey,TA
DOI：
10.1073/pnas.93.11.5584
发表时间：
1996-05-28
影响因子：
11.1
作者：
Fox, K;Schlaggar, BL;OLeary, DDM
通讯作者：
OLeary, DDM