Development of the dendritic branching pattern of the medial giant interneuron in the grasshopper embryo.
Development of the dendritic branching pattern of the medial giant interneuron in the grasshopper embryo.
复制标题
蚱蜢胚胎内侧巨型中间神经元树突状分支模式的发育。
DOI：
10.1016/0012-1606(82)90194-4
复制
发表时间：
1982
影响因子：
2.7
通讯作者：
Goodman,CS
中科院分区：
文献类型：
--
作者：
Shankland,M;Goodman,CS
采用荧光染料路西法黄（Lucifer Yellow）对蝗虫内侧巨中间神经元（Medial Giant Interneuron， MGI）的胚胎发育进行了观察。特别要注意的是，这个神经元构建其树突分支模式的方式。MGI的树突起源于次生过程，在初级生长锥体通过后沿着神经突的特征点萌发。在胚胎生命结束之前，这些过程形成了一个成年分支模式的微型版本。在生长过程中，树突树枝上覆盖着大量的丝状伪足；然而，这些丝状足是短暂的结构，一旦细胞成熟就会消失。相比之下，在任何胚胎阶段，实际树突的数量或空间范围都没有明显减少。这意味着成熟MGI的定型分支模式主要是由初始生长的精确模式决定的，分支的二次修剪在形成该细胞的最终形式中并不起重要作用。用钴填充胚胎神经的方法研究了第一批感觉轴突的坐标生长，并讨论了这些感觉轴突与MGI树突的初始接触方式。下面的文章考虑了这种感觉神经支配树突生长和分支的程度。
The embryonic development of the grasshopper's Medial Giant Interneuron (MGI) was examined by injecting the cell with the fluorescent dye Lucifer Yellow at a series of stages in its growth. Particular attention was given to the way in which this neuron constructs its stereotyped dendritic branching pattern. The MGI's dendrites originate as secondary processes which sprout at characteristic points along the neurite after the primary growth cone has passed. These processes then arborize to form a miniature version of their adult branching pattern before the end of embryonic life. While growing, the dendritic branches are covered with a radiant profusion of filopodia; however, these filopodia are ephemeral structures and disappear once the cell matures. By contrast there is no significant reduction in either the number or the spatial extent of the actual dendrites at any embryonic stage. This implies that the stereotyped branching pattern of the mature MGI is primarily determined by a precise pattern of initial growth, and that secondary pruning of branches does not play an important role in shaping the final form of this cell. The coordinate ingrowth of the first cercal sensory axons was examined by cobalt filling the embryonic nerve, and the means by which these sensory axons make their initial contacts with the MGI's dendrites is herein discussed. The following paper considers the degree to which this sensory innervation regulates dendritic growth and branching.