The Modulation of Inhibitory Synapses During Development

9308377随着大脑的成熟，神经细胞之间的连接会随着环境的变化而逐渐改变，类似于学习和记忆的基本机制。一些神经细胞之间的连接变得更强，而另一些则被完全消除。发生这些变化的机制开始在中枢神经系统中的一组连接上被解开，这组连接被称为兴奋性连接。这组连接是运动神经元和肌肉细胞之间的那种连接，其中一个细胞激活另一个细胞。然而，大脑中近一半的神经元连接是抑制性的，我们还不知道这些连接在中枢神经系统的发育过程中是否被修改。由于大脑执行的几乎每一项任务都利用兴奋性和抑制性连接，了解后者是如何发展的是至关重要的。这项拟议的研究将调查抑制性连接的强度是否依赖于大脑成熟过程中的经验。在中枢听觉系统中，可以通过检查刺激时电反应的大小来监测已识别的抑制性连接的强度。该项目将确定在发育过程中使用或不使用这些抑制连接时，它们的电活动会发生什么。在分子水平上，当这些连接保持沉默时，将有可能确定是否产生了适当数量的介导抑制活性的受体分子。第二个实验将确定是否可以通过以非常高的水平直接刺激抑制性连接，在几分钟内增强它们的强度。总而言之，这些实验将展示抑制连接的修改如何导致成熟的中枢神经系统功能。*CI Sound midimap.drv=MIDI Mapper timer.drv=Timer Rv=Timer v=Timer timer.drv=Timer imer.dr9308377随着大脑的成熟，神经细胞之间的连接随着环境的变化而逐渐改变。！！！F(Times New Roman Symbol&amp；Arial“h$E‘E 1#@Sanes William Proctor，IBN William Proctor，IBN

9308377 Sanes As the brain matures, the connection between nerve cells are gradually modified in response to the environment, similar to the mechanisms underlying learning and memory. Some of the connections between nerve cells become stronger, while others are eliminated altogether. The mechanisms by which these changes occur are beginning to be unraveled at one set of connections in the central nervous system, called excitatory connections. This set of connections is the sort found between a motor neuron and muscle cell, where one cell activates a second. However, nearly half of the neuronal connections in the brain are inhibitory, and we do not yet know whether these connection are modified during the development of the central nervous system. Since virtually every task that the brain performs utilizes both excitatory and inhibitory connections, it is essential to understand how the latter develop. The proposed study will investigate whether the strength of inhibitory connections is dependent upon experience during the course of brain maturation. In the central auditory system, it is possible to monitor the strength of identified inhibitory connections by examining the size of the electrical response when they are stimulated. This project will determine what happens to the electrical activity at these inhibitory connections when they are used or not used during the course of development. At a molecular level, it will be possible to determine whether the receptor molecules that mediate inhibitory activity are produced in appropriate number when these connections remain silent. A second experiment will determine whether the strength of inhibitory connections can be enhanced over the course of minutes by directly stimulating them at very high levels. Together, these experiments will demonstrate how the modification of inhibitory connections may lead to mature central nervous system function. *** CI Sound midimap.drv=MIDI Mapper timer.drv=Timer rv=Timer v=Timer timer.drv=Timer imer.dr9308377 Sanes As the brain matures, the connection between nerve cells are gradually modified in response to the environment ! ! ! F ( Times New Roman Symbol & Arial " h $ EÕ E 1 # @ sanes William Proctor, IBN William Proctor, IBN