CHOLINOCEPTIVE NEURONS IN THE VERTEBRATE RETINA

对存在于脑内的递质和受体的了解 脊椎动物的视网膜对于试图理解视网膜是必不可少的 功能。乙酰胆碱(ACh)是一种已知的神经递质 在脊椎动物的视网膜中，关于这种分布的许多信息都是已知的 和胆碱能无长突细胞的形态，释放 ACh，以及ACh对某些神经节细胞的影响。 以前对胆碱能感受性细胞的研究依赖于 甲型银环蛇毒素。然而，最近的研究表明，这一点 毒素识别一种与ACh受体分离的蛋白质。 因此，毒素结合的模式不能再被认为是 代表ACh受体的分布。 拟议研究的总体目标是确定和 描述视网膜中胆碱能神经元的特征，阐明 他们的发展，并了解他们与 胆碱能突触前细胞。具体目标和方法 要实现这些目标，请遵循以下原则。 1)含有ACh受体的细胞将被鉴定并 其特点是使用针对 ACh受体。这项技术将揭示它们的数量和 的分布及其树枝状分枝模式 发育中的和成年的视网膜。 2)胆碱能感受性神经节细胞投射到特定的 中央视网膜核将用一种 免疫组织化学与注射用药相结合 逆行将标记转移到特定的视网膜上 原子核。 3)胆碱能神经元的大小、形态和层状结构 树枝状区域将由以下各项组合确定 单个神经元的细胞内填充和免疫组织化学。 染料注入揭示的树枝状图案将是 与免疫组织化学相比。 4)细胞数量和树枝状分枝模式 胆碱能细胞将与胆碱能细胞进行比较。 用免疫组织化学方法检测神经元。此外，研究还包括 胆碱能细胞的发育 胆碱能感受性细胞也将以同样的方式进行研究。

Knowledge of the transmitters and receptors present in the vertebrate retina is essential to attempts to understand retinal function. Acetylcholine (ACh) is known to be a neurotransmitter in the vertebrate retina and much is known about the distribution and morphology of the cholinergic amacrine cells, the release of ACh, and the effects of ACh on some types of ganglion cells. Previous studies of the cholinoceptive cells have relied upon alpha-bungarotoxin. Recent studies have shown, however, that this toxin recognizes a protein which is separate from the ACh receptor. Thus, the pattern of toxin binding can no longer be considered to represent the ACh receptor distribution. The overall objectives of the proposed research are to identify and characterize the cholinoceptive neurons in the retina, elucidate their development, and to understand their relationship to the cholinergic presyaptic cells. The specific aims and the methods to achieve them follow. 1) Cells containing ACh receptors will be identified and characterized by using monoclonal antibodies directed against the ACh receptors. This technique will reveal their numbers and distribution, and their dendritic branching pattern in both the developing and adult retina. 2) The cholinoceptive ganglion cells that project to specific central retinorecipient nuclei will be characterized using a combination of immunohistochemistry and the injection of retrogradely transported markers into specific retinorecipient nuclei. 3) The size, shape and laminar pattern of cholinoceptive neurons' dendritic fields will be determined by a combination of intracellular filling of single neurons and immunohistochemistry. The dendritic patterns as revealed by the dye injection will be compared to that seen with immunohistochemistry. 4) The numbers of cells and dendritic branching pattern of the cholinoceptive cells will be compared to those of the cholinergic neurons using immunohistochemical methods. In addition, studies of the development of the cholinergic cells relative to that of the cholinoceptive cells will be studied in the same way.