Optical Analysis of Synaptic Integration in Cerebellar Purkinje Cells

[9514266 .罗斯]中枢神经系统通常看起来像一排密集的、令人眼花缭乱的神经元和神经元突触的相互作用。部分问题在于突触在细胞上的特定位置的功能意义在很大程度上是未知的。这项基金资助的研究重点是确定浦肯野细胞突触空间排列的重要性，浦肯野细胞是小脑中最大的神经元，也是向大脑其他部分提供唯一输出的神经元。这个焦点涉及到浦肯野细胞输入区、树突和这些神经元结构中电压依赖的膜电导如何影响整合过程的复杂问题。实验旨在确定这些突触输入的空间模式的功能意义。主要技术是通过在脑组织切片中使用指示染料来光学记录钙浓度。钙浓度，当结合电记录时，是整个神经元细胞内电位变化的良好指标，因此是局部神经元活动的指标。小脑皮层相对刻板的电路为详细研究细胞几何和突触相互作用的功能意义提供了良好的模型系统。这些研究应该提供非常需要的，详细的描述突触相互作用在至关重要的小脑神经元。这样的描述将在单细胞水平上大大提高对哺乳动物神经元信息处理的认识。

9514266 Ross The central nervous system often appears like a dense, bewildering array of neurons and of neuronal synaptic interactions. Part of the problem is that the functional significance of specific locations at which synapses occur on cells is largely unknown. The focus of research funded by this grant is on determining the significance of the spatial arrangement of synapses on Purkinje cells, which are the largest neurons in the cerebellum and which provide the only output to other parts of the brain. This focus relates to the complex problem of how voltage-dependent membrane conductances in Purkinje cell input regions, the dendrites, and the architecture of these neurons influence the integration process. Experiments are designed to determine the functional significance of the spatial patterns of these synaptic inputs. The primary technique is optical recording of calcium concentrations through the use of indicator dyes in slices of brain tissue. Calcium concentrations, when combined with an electrical recording, are good indicators of changes in intracellular potentials throughout neurons and hence of local neuronal activity. The relatively stereotyped circuitry of the cerebellar cortex provides a favorable model system for studying the functional significance of cell geometry and synaptic interactions in detail. These studies should provide much needed, detailed descriptions of synaptic interactions in critically important cerebellar neurons. Such descriptions will greatly enhance knowledge of information processing in mammalian neurons at the single cell level.