REGULATION OF NEURITE OUTGROWTH AND CONNECTIVITY

电活动在交流中起着重要作用 沿着神经细胞。 长期以来人们一直认为脑电活动 可能在控制神经元形态方面发挥更广泛的作用 和连通性。 最近的行动表明， 抑制神经突生长的潜力现在提供了概念上的 这些无处不在的信号可以直接影响 神经元结构和神经回路的形成。 目标 该提案的目的是确定电活动的作用， 调节神经元的形态和连接，并表明， 这些效应可能是由生长过程中的钙变化介导的 圆锥体。 特别注意的是， 调节伸长顶端生长锥的运动 神经突 这些实验利用高分辨率系统， 从蜗牛Helisoma中发现了神经元， 其特征在于它们的正常形态、生物物理 特性以及与其他神经元的连接。 细胞体 识别出的神经元将从其正常的 神经节环境，并置于细胞培养物中，以促进 神经突的定量时空测量 结果 细胞体将被直接电刺激 以及对大型生长锥的影响， 本物种的数量将进行定量评估，以测试如何：1） 电信号的综合特性影响生长， 神经元的最终形态，2）神经元中的电信号 回路可以对神经元施加全局和局部控制， 形态学，3）电活动影响突触发生，以及4） 生长锥钙的变化可能介导这些效应。 这些发现将建立神经元结构与 功能 他们将深入了解神经元的调节 架构和连通性，这是建立 成人神经回路

Electrical activity plays a fundamental role in communication along nerve cells. It has long been thought that electrical activity might play a much broader role in the control of neuronal form and connectivity. The recent demonstration that action potentials inhibit neurite outgrowth now provides the conceptual link whereby these ubiquitous signals can directly influence neuronal structure and the formation of neural circuits. The aims of the proposal are to determine the role of electrical activity in regulating neuronal morphology and connectivity and to show that these effects may be mediated by calcium changes in growth cones. Specific attention is given to how electrical activity regulates the movements of growth cones at the tips of elongating neurites. These experiments utilize a high resolution system of identified neurons from the snail Helisoma which are uniquely characterized in terms of their normal morphology, biophysical properties, and connections with other neurons. Cell bodies of identified neurons will be individually removed from their normal ganglionic environment and placed in cell culture to facilitate quantitative spatial and temporal measurements of neurite outgrowth. Cell bodies will be electrically stimulated directly and the effects on the large growth cones that are characterized of this species will be quantitatively assessed to test how: 1) integrative properties of electrical signals affect outgrowth and the final morphology of neurons, 2) electrical signals in neural circuits may exert both global and local control over neuronal morphology, 3) electrical activity affects synapotogenesis, and 4) changes in growth cone calcium may mediate these effects. These findings will establish a link between neuronal structure and function. They will provide insight into the regulation of neuronal architecture and connectivity which underlie the establishment of adult neuronal circuits.