NEURAL CONTROL OF MAGNOCELLULAR NEUROENDOCRINE CELLS

我们研究的长期目标是了解 参与控制大细胞分泌激素 神经内分泌细胞（MNCs），其细胞体主要位于 视上核（SON）和室旁核（PVN）。 由于电活动的模式是脑电活动的主导因素， 这些细胞的神经分泌过程，我们的直接目标， 这里提出的研究是调查一些因素， 影响或决定其活动模式。 我们特别希望 专注于研究膜特性，突触输入和 非突触的相互作用，所有这些都可能在控制 或者调节这个系统中的神经分泌过程。 为了实现这些目标，我们将记录细胞内从 室旁核和穹窿周围神经元以及从神经元和胶质细胞中的 大鼠下丘脑切片中SON的面积。 在一些情况下 电极将填充荧光染料，荧光黄（LY）， 在其他人与辣根过氧化物酶（HRP），以确定 记录细胞并追踪其过程。 用LY标记的细胞将经历 或者随后的激素含量的免疫细胞化学分析（催产素， 加压素或脑啡肽）或电子显微镜（EM）分析， 在使LY电子致密之后，显示间隙连接。 HRP注射细胞及其过程将在两个光分析 和EM水平，以确定侧支和轴突 这些神经元的末端。 对假定的递质的研究也将 执行。 因此，我们将能够确定生理， 这一脑区细胞的形态和激素特征， 以及了解更多关于这些细胞群的局部电路 显然参与。

The long-range goal of our research is to understand the mechanisms involved in the control of hormone secretion from the magnocellular neuroendocrine cells (MNCs) whose cell bodies reside predominantly in the supraoptic (SON) and paraventricular (PVN) nuclei of the hypothalamus. Since the patterns of electrical activity are dominant factors in the process of neurosecretion by these cells, our immediate goals for the research proposed here are to investigate some of the factors which may influence or determine their activity patterns. In particular we wish to focus on investigating membrane properties, synaptic inputs and non-synaptic interactions, all of which probably play roles in controlling or modulating the process of neurosecretion in this system. In order to accomplish these objectives, we will record intracellular from PVN and perifornical neurons and from both neurons and glial cells in the area of the SON in slices of rat hypothalamus. In some instances the electrodes will be filled with the fluorescent dye, Lucifer Yellow (LY), and in others with horseradish peroxidase (HRP) in order to identify the recorded cell and trace its processes. Cells marked with LY will undergo either subsequent immunocytochemical analysis of hormone content (oxytocin, vasopressin or enkephalin) or electron microscopic (EM) analysis to demonstrate gap junctions after rendering the LY electron dense. HRP-injected cells and their processes will be analyzed at both the light and EM levels in order to determine the collateral branching and axonal terminations of these neurons. Studies of putative transmitters will also be carried out. Thus, we will be able to determine the physiological, morphological and hormonal characteristics of cells in this brain area, as well as to learn more about the local circuitry in which these cell groups apparently participate.