SYNAPTIC SPECIFICITY IN THE SPINAL CORD

这些研究的长期目标是确定 参与介导的神经终末膜成分 脊髓中特殊的突触连接 成分 神经末梢表面质膜广泛地 据信在形成过程中起着至关重要的作用， 突触连接的维持。 据推测，具体 不同群体脊髓神经元之间的突触关系 传入神经末梢的差异反映在 突触前膜的组成。 但 独特的突触前膜蛋白参与介导 具体的突触连接尚待鉴定。 单克隆 针对突触膜抗原的抗体具有 已经开发出了识别突触前膜蛋白 与脊神经末梢相连 虽然其中许多 抗体识别突触末端的普遍存在的组分， 其他的是脊髓传入神经亚群特有的 terminals. 其中一种特别针对突触 囊泡膜抗原，它似乎有一些 突触前膜蛋白的预期特性 参与调节特定的突触连接。 的目的 拟议的研究是：1）确定 这种抗原在发育过程中在脊髓中的表达 包括抗原的超微结构定位， 脊髓背角的突触发生; 2）确定起源 含有抗原的脊髓神经元通路， 确定这些神经元中假定的神经递质; 3） 绘制抗原在中央其他部位的分布图 和周围神经系统和非神经元分泌 细胞; 4）确定该抗原的相关程度 与神经末梢质膜，特别是与 突触连接区和突触间隙; 5） 表征抗原以确定其是否是 6）纯化抗原 并开发出单特异性的多克隆抗血清。 研究的第二部分将旨在确定其他 神经末梢突触质膜蛋白，其可以 参与调节脊髓中的突触特异性。 光镜和电镜免疫细胞化学方法， 沿着各种免疫化学程序将被用于 这些调查。 这些研究的结果很可能 对理解这些机制有重要意义 参与突触的形成和维持 脊髓的连接

The long term goal of these studies is the identification of the nerve terminal membrane components involved in mediating specific synaptic linkages in the spinal cord. Constituents of the nerve terminal surface plasma membrane are widely believed to have a crucial role in the formation and maintenance of synaptic connections. Presumably, the specific synaptic relationships formed by different populations of spinal afferent nerve terminals are reflected by differences in the composition of their presynaptic membranes. However, the unique presynaptic membrane proteins involved in mediating specific synaptic linkages are yet to be identified. Monoclonal antibodies directed against synaptic membrane antigens have been developed which identify presynaptic membrane proteins associated with spinal nerve terminals. While many of these antibodies recognize ubiquitous components of synaptic endings, others are specific to subpopulations of spinal afferent nerve terminals. One in particular is directed against a synaptic vesicle membrane antigen which appears to have some of the properties expected of a presynaptic membrane protein involved in mediating specific synaptic linkages. The aims of the proposed studies are to: 1) determine the time course of expression of this antigen in the spinal cord during development including, ultrastructural localization of the antigen during synaptogenesis in the spinal dorsal horn; 2) identify the origins of the spinal neuronal pathways which contain the antigen and determine the putative neuro-transmitter(s) in these neurons; 3) map the distribution of the antigen in other parts of the central and peripheral nervous system and in non-neuronal secretory cells; 4) determine to what extent this antigen is associated with the nerve terminal plasma membrane and specifically with the synaptic junctional region and synaptic cleft; 5) characterize the antigen the determine whether it is a peripheral or integral membrane protein 6) purify the antigen and develop a monospecific, polyclonal antiserum to it. A second part of the studies will be directed at identifying other nerve terminal synaptic plasma membrane proteins which may be involved in mediating synaptic specificity in the spinal cord. Immunocytochemical methods for light an electron microscopy, along with various immunochemical procedures will be used in these investigations. The results of these studies are likely to have significant implications for understanding the mechanisms involved in the formation and maintenance of synaptic connections in the spinal cord.