ULTRASTRUCTURAL DEVELOPMENT OF ANTENNAL CENTER

神经元之间以及神经元和神经胶质细胞之间的相互作用已经被证实。 许多研究人员表明，这对正常发育至关重要。 神经系统 这项研究是一项发展性的研究， 神经元和神经胶质细胞之间的相互作用 母亲的系统，在那里大部分发育发生在胚后。 目前对天蛾触角系统的研究表明， 就像在脊椎动物中一样，感觉轴突引导着大脑的许多方面。 在这种情况下，他们的目标，触角叶， 个脑袋 拟议研究的目标是了解在一个细胞 水平的性质的影响所施加的触角感觉轴突。 以前的工作表明，触角轴突的影响， 神经元的形态组织， 的神经胶质细胞，和突触的分布在触角叶。 有几条线索的证据导致的假设，神经胶质细胞的 脑叶可能充当感觉轴突之间的中介， 二级触角叶神经元在其中一些相互作用。 我们 我建议主要用两个实验模型来检验这一假设： 触角叶已经被剥夺了触角轴突整个 发育，和触角叶，其中胶质细胞的数量已经 严重减少，通过暴露于伽马辐照在关键 胶质细胞增殖的阶段。 特色发展 小叶内的神经球、突触的分布和数目 叶，和发展的分支模式的个人 将监测触角叶神经元并与正常进行比较。 如果 神经胶质缺乏的叶类似于任何这些无神经支配的叶， 参数（如初步实验所示），这将是 被解释为神经胶质细胞是流动的必要通道的证据 从感觉轴突到触角叶神经元的指令信息。 这些参数依赖于感觉轴突的存在，而不是 神经胶质的存在将被解释为最有可能是由于 直接神经元间的相互作用

Interactions between neurons and between neurons and glial cells have been shown by a number of researchers to be critical for normal development of the nervous system. The proposed research is a study of developmental interactions among neurons and glial cells in the forming central nervous system of a moth, where much of development occurs postembryonically. Current work on the antennal system of the moth Manduca sexta suggests that, just as in vertebrates, sensory axons guide many aspects of the development of their targets, in this case, the antennal lobes of the brain. The goal of the proposed research is to understand at a cellular level the nature of the influence exerted by the antennal sensory axons. Previous work has indicated that the antennal axons influence the morphological organization of the neuropil, the disposition and morphology of glial cells, and the distribution of synapses in the antennal lobe. Several lines of evidence lead to the hypothesis that the glial cells of the lobe may be acting as intermediaries between sensory axons and second-order antennal-lobe neurons in some of these interactions. We propose to test this hypothesis using primarily two experimental models: antennal lobes that have been deprived of antennal axons throughout development, and antennal lobes in which the number of glial cells has been severely reduced through exposure to gamma-irradiation during critical stages of glial proliferation. The development of the characteristic glomeruli of the lobe, the distribution and numbers of synapses in the lobe, and the development of the branching patterns of individual antennal-lobe neurons will be monitored and compared with normal. If glial-deficient lobes resemble uninnervated lobes in any of these parameters (as preliminary experiments indicate they may), this will be interpreted as evidence that glial cells were a necessary conduit for flow of insstructive information from sensory axons to antennal-lobe neurons. Parameters that do depend upon the presence of sensory axons but not upon the presence of glia will be interpreted as resulting most likely from direct neuron-neuron interactions.