Target neuron-specific process formation by embryonic mesencephalic dopamine neurons in vitro.
Target neuron-specific process formation by embryonic mesencephalic dopamine neurons in vitro.
复制标题
体外胚胎中脑多巴胺神经元的目标神经元特异性过程形成。
DOI：
10.1073/pnas.78.2.1264
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发表时间：
1981
影响因子：
11.1
通讯作者：
Heller,A
中科院分区：
文献类型：
--
作者：
Hemmendinger,LM;Garber,BB;Hoffmann,PC;Heller,A
从胚胎小鼠脑中脑多巴胺神经元的解离，聚集在体外的解离细胞从适当或不适当的目标神经元区域的存在下，和可视化的Falck-Hillarp组织荧光技术后，暴露于1 μ M外源性多巴胺。当仅与周围的中脑被盖头端细胞或与顶盖头端细胞聚集时，多巴胺神经元形成密集的树突状分支，但没有观察到轴突。在纹状体多巴胺神经元靶细胞的存在下，观察到在体内该区域形成的致密轴突丛特征。相反，在与来自额叶皮质的靶细胞形成的聚集体中，发现具有不规则间隔和形状的静脉曲张的分支荧光轴突穿过神经节，这是体内额叶皮质的多巴胺能神经支配的特征。在这些轴突靶细胞的存在下，仅观察到近端树突。不适当的靶细胞培养的多巴胺神经元从枕叶皮质没有形成广泛的轴突或树突的过程。因此，多巴胺神经元过程的存在、类型和分布取决于适当靶细胞的存在。在体外分离的神经元形成独特的神经元过程模式表明，这种分化所需的信息是固有的多巴胺神经元和它们的靶细胞。该系统为研究神经元识别的基本机制提供了一个有用的模型。
Mesencephalic dopamine neurons from the embryonic mouse brain were dissociated, aggregated in vitro in the presence of dissociated cells from appropriate or inappropriate target neuron areas, and visualized by the Falck-Hillarp histofluorescence technique after exposure to 1 microM exogenous dopamine. When aggregated with the surrounding rostral mesencephalic tegmentum cells only or with the addition of rostral tectum cells, the dopamine neurons formed a dense dendritic arborization, but no axons were observed. In the presence of dopamine-neuron target cells from the corpus striatum, a dense axonal plexus characteristic of that formed in this area in vivo was observed. In contrast, in aggregates formed with target cells from the frontal cortex, branching fluorescent axons bearing irregularly spaced and shaped varicosities were found coursing through the neuropil, as is characteristic of the dopaminergic innervation to the frontal cortex in vivo. Only proximal dendrites were observed in the presence of these axonal target cells. Dopamine neurons cultured with inappropriate target cells from the occipital cortex did not form either extensive axonal or dendritic processes. Thus, the presence, type, and distribution of dopamine neuronal processes are dependent on the presence of appropriate target cells. The formation of unique patterns of neuronal processes by dissociated neurons in vitro suggests that the information necessary for this differentiation is intrinsic to the dopamine neurons and their target cells. This system provides a useful model with which to study basic mechanisms underlying neuronal recognition.