EFFECTS OF DC FIELDS ON VERTEBRATE NEURONS

直流电场被认为可以刺激轴突再生和生长。 轴突，因此被认为是一种诱导轴突的方法 神经损伤后的再生。如果为真，则此类应用 菲尔德在治疗神经损伤方面可能很重要。尽管有几个 已有研究报道使用直流电磁场治疗脊椎和 在动物周围神经损伤方面，有各种各样的担忧 这些研究中的每一项都离开了普通科学界 对调查结果持怀疑态度。相比之下，轴突的一般现象 文化中向电场的取向、生长和迁移 都是老牌的。虽然有可能毫不含糊地 在体外展示了电流响应，类似的效果已经被 很难在体内可靠地生产。DC场具有低信息量 内容，并且只能为细胞提供定向或刺激提示。 这些提示中的任何一种都是通过偏置细胞的一侧来调节的 离子通道、膜受体、膜电位等术语。 一个培养盘的统一环境，一个应用领域可能是唯一的 不对称影响，因此可能对细胞产生重大影响 行为。然而，在活体条件下，有各种竞争 细胞行为的信号，如扩散因子的梯度，细胞到 细胞相互作用，以及底物粘附性的梯度。在这 在这种情况下，电场提供的轻微方向偏置可能是 无关紧要。 拟议研究的长远目标是确定 外加磁场对体外培养细胞的作用机制及作用机制 确定这种机制在活体情况下是否起作用。 具体目标是； 1.比较生长在单细胞和单细胞上的鸡神经元的电流反应。 复杂的底物。 2.确定发育阶段对反应的影响。 3.考察细胞类型和底物来源对反应的影响。 4.发展有系统和可靠地执行这类工作的手段 实验。 为了验证这一假说，我们将检验神经元的电流反应。 在复杂的培养条件下，如切片培养。这些条件 保持体外实验的可控性、可获得性和可操作性 条件，但提供了一个复杂的环境来模拟体内的自然 情况变得更紧密。基本方法是获取延时视频 响应于外加的直流场的单个单元。单元格将要么 被荧光标记的细胞种植在复杂的底物上，或者 通过显微注射填充的组织切片中的细胞。 利用荧光视频显微镜，我们将制作单个细胞的图像。 在高倍率下。显微镜台上的步进电机将会移动 在多个预选单元格之间切换，并在调整时间获取图像 间隔时间。这些图像将被重新组合成详细说明的视频序列 然后将对每个细胞的行为进行统计分析。

DC electric fields are thought to stimulate axonal regeneration and growing axons, and so have been suggested as a method for inducing axonal regeneration following nerve injuries. If true, the application of such fields could be important in treating nerve injuries. Although several studies have reported the use of DC fields as a treatment for spinal and peripheral nerve injuries in animals, there are a variety of concerns with each of these studies that have left he general scientific community skeptical of the findings. In contrast, the general phenomena of axonal orientation, growth, and migration towards an electric field in cultaure are well established. While it has been possible to unequivocally demonstrate galvanic responses in vitro, comparable effects have been difficult to produce reliably in vivo. DC fields have low information content and can only provide cells with a directional or stimulatory cue. Either of these cues would be mediated by biasing one side of the cell in terms of ion channels, membrane receptors, membrane potential, etc. In the uniform environment of a culture dish, an applied field may be the only asymmetric influence, and thus may have a significant effect on cellular behavior. In in vivo condiitons, however, there a variety of competing signals for cell behavior such as gradients of diffusible factors, cell to cell interactions, and gradients of substrate adhesiveness. In this situation, the slight directional bias supplied by an electric field may be inconsequential. The long term objectives of the proposed study are to determine the mechanism of the effect of applied fields on cells in vitro and to determine if such a mechanism is functional in the in vivo situation. Specific aims are to; 1. compare the galvanic response of chick neurons grown on simple and complex substrates. 2. determine the effect of developmental stage on the response. 3. examine the effects of cell type and substrate source on the response. 4. to develop the means for systematically and reliable performing such experiments. To test this hypothesis, the galvanic response of neurons will be examined in complex culture conditions such as slice culture. These conditions retain the control, accessibility, and manipulability of the in vitro condition but provide a complex environment ot simulate the natural in vivo situation more closely. The basic method is to acquire time lapse videos of individual cells responding to applied DC fields. The cells will either be fluorescently labeled cells seeded on top of a complex substrate, or cells within a tissue slice that have been dye filled by microinjections. Using fluorescence videomicroscopy, images of individual cells will be made at high magnification. Stepper motors ont he microscope stage will move between many preselected cells and acquire images at regulate time intervals. These images will be recombined into a video sequence detailing the behavior of each cell that will then be statistically analyzed.