大鼠纹状体边缘区与Meynert氏基底核的突触联系及其与学习记忆功能的关系——WGA-HRP束路追踪法、电镜法和行为实验法研究

SYNAPTIC CONNECTIONS BETWEEN THE PROJECTION FROM THE MARGINAL DIVISION OF THE STRIATUM TO THE MEYNERT'S BASAL NUCLEUS AND ITS RELATIONSHIP TO THE LEARNING AND MEMORY BEHAVIOR OF THE RAT

纹状体边缘区（ＭｒＤ）是我们先后在大鼠、猫和猴脑内新发现的一个区域。它是位于纹状体尾内侧、环绕着苍白球头外侧的一层梭形细胞。ＭｒＤ的细胞构筑、免疫组化特性和纤维联系形式不同于纹状体其它区。ＭｒＤ的离心投射终止在苍白球尾侧，接近Ｍｅｙｎｅｒｔ基底核（ＮＢＭ）附近。损毁双侧ＭｒＤ后，动物的学习记忆功能减弱。ＮＢＭ已知与动物智能有关。本研究用纤维溃变和束路追踪电镜法结合行为实验方法，旨在了解ＭｒＤ与ＮＢＭ之间有无突触联系，以及此种联系与动物学习记忆的关系。用纤维溃变和束路追踪电镜法研究表明，由ＭｒＤ发出的纤维终末与ＮＢＭ的胆碱能神经元胞体间存在着突触联系。损伤ＭｒＤ造成ＭｒＤ和ＮＢＭ形成突触联系的终末溃变后，动物的学习记忆能力降低。研究结果表明边缘区与Ｍｅｙｎｅｒｔ基底核间存在着突触联系，而这种联系很可能是ＭｒＤ的学习记忆功能的结构基础之一。

The marginal division(MrD) is a layer of fusiform neurons located at the caudomedial border of the striatum surrounding the rostrolateral edge of the globus pallidus. It has been confirmed that the MrD exists in the striatum of the rat, cat and monkey brain. The MrD differs from the main body of the striatum in the cellular architecture, neurochemistry and connection patterns. The efferent projection from the MrD terminates at the caudal part of the globus pallidus near the basal nucleus of the Meynert (NBM). Depression of learning and memory behavior occurred following chemical lesion of MrD in the rat striatum. The expression of oncogene c Fos protein was observed in the basal nucleus of Meynert and limbic system following chemial stimulating the MrD. The aim of this study is to investigate the synaptic characteristics of the projection from the MrD to the NBM, and its relationship to the learning and memory function by using a combination of neurochemical, tract tracing, electric microscopy, and behavior study methods. Synaptic connections were found between the terminals from the MrD and the cholinergic cellular bodies of the basal nucleus of Meynert. Depression of learning and memory behavior happened with the terminal degeneration of the MrD NBM projection. It is assumed that there are synaptic connections from MrD to NBM and these connections probably contributes to the learning and memory function of the rat.