Afferent innervation shapes the dendritic branching pattern of the medial giant interneuron in grasshopper embryos raised in culture.
Afferent innervation shapes the dendritic branching pattern of the medial giant interneuron in grasshopper embryos raised in culture.
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传入神经支配塑造了培养中的蚱蜢胚胎内侧巨型中间神经元的树突分支模式。
DOI：
10.1016/0012-1606(82)90195-6
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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;Bentley,D;Goodman,CS
在成虫体内，内侧巨细胞中间神经元(MGI)接受来自颈椎外周感觉神经元的突触输入。在蝗虫胚胎中，我们通过在第一感觉轴突刚刚开始到达中枢神经系统(CNS)时切断一个或两个宫颈来防止这种神经支配，而MGI尚未形成其成熟的分支模式。手术后，将胚胎在体外培养3-9天，并向MGI注射荧光染料荧光黄以确定其形态。然后将剥夺的细胞的发育与正常的MGI(在M.Shankland和C.S.Goodman，1982，Development中描述的)进行比较。Biol.，92,483-500)和培养的但未手术的对照，以确定这些突触前轴突是否影响MGI树突的胚胎生长和分支。这些实验的结果表明，在含有感觉神经轴突终末的神经束区域，树突的形成得到促进，传入神经对分支结构的受限部分产生了局部影响。神经支配的树突的加速生长似乎是以牺牲其他地方的树突生长为代价的，这表明正在生长的树突可能在竞争有限的细胞成分的供应，这些细胞成分是持续生长所必需的。因此，MGI的最终分支模式至少部分取决于胚胎神经系统内突触前轴突的空间分布。
In the adult grasshopper the Medial Giant Interneuron (MGI) receives synaptic input from the peripheral sensory neurons of the cercus. We prevented this innervation in grasshopper embryos by cutting off one or both cerci at a stage when the first sensory axons are just beginning to reach the central nervous system (CNS), and the MGI has not yet formed its mature branching pattern. Following this operation the embryos were raisedin vitrofor 3–9 days, and the MGI injected with the fluorescent dye Lucifer Yellow to determine its morphology. The development of the deprived cells was then compared to that of the normal MGI (described in M. Shankland and C. S. Goodman, 1982,Develop. Biol.,92,483–500) and of cultured, but unoperated, controls to ascertain whether these presynaptic axons influence the embryonic growth and branching of the MGI's dendrites. The results of these experiments show that dendrite formation is enhanced in regions of the neuropil containing sensory axon terminals and that the afferents exert their influence locally on restricted portions of the branching structure. The enhanced growth of innervated dendrites appears to occur at the expense of dendritic outgrowth elsewhere, suggesting that the growing dendrites may be competing for a limited supply of some cellular component necessary for continued growth. Thus, the MGI's final branching pattern is at least partially dictated by the spatial distribution of presynaptic axons within the embryonic nervous system.