OPTICAL ANALYSIS OF THE REGIONAL PROPERTIES OF NEURONS

我们将研究突触整合，区域膜特性， 食管上神经节神经元内钙的控制 巨大的藤壶，藤壶nubilus和口胃神经节的 螃蟹，巨蟹座。 这些问题的许多有趣方面 发生在这些细胞的树突或突触前末梢上， 因此不能容易地用微电极检查。 因此我们 将采用我们一直在开发的光学方法来检查这些 以前无法到达的地区。 使用电压敏感染料和 钙指示剂染料，我们将绘制电位的分布， 钙瞬变的特性同时贯穿这些神经元。 从这些测量中，我们将确定被动膜的性能 在许多地方，离子传导机制的区域变化， 突触位置和突触和动作电位的传播 牢房 此外，钙瞬变的阈值和时间过程 将进行检查，以揭示钙的性质的区域变化 通道和钙缓冲机制。 我们开发的技术 我们得出的结论应该具有普遍的价值， 细胞和突触机制在各种各样的准备，从 从培养的单个神经元到哺乳动物大脑中的神经元。

We will study synaptic integration, regional membrane properties, and control of internal calcium in neurons of the supraesophageal ganglion of the giant barnacle, Balanus nubilus and the stomatogastric ganglion of the crab, Cancer borealis. Many of the interesting aspects of these problems occur on the dendrites or presynaptic terminals of these cells and therefore cannot be easily examined with microelectrodes. Therefore we will employ optical methods which we have been developing to examine these previously inaccessible regions. Using both voltage sensitive dyes and calcium indicator dyes we will map the spread of electrical potentials and properties of calcium transients simultaneously throughout these neurons. From these measurements we will determine the passive membrane properties at many locations, regional variations in ionic conductance mechanisms, synapse locations and the propagation of synaptic and action potentials in the cell. In addition, the threshold and time course of calcium transients will be examined to reveal regional variations in the properties of calcium channels and calcium buffering mechanisms. Both the techniques we develop and the conclusions we reach should be of general value in understanding cellular and synaptic mechanisms in a wide variety of preparations, from single neurons in culture to neurons in the mammalian brain.