NEURONAL CONNECTIONS AND RESPONSES IN CINGULATE CORTEX

本研究的目的是评估内在组织， 扣带皮层神经元的受体结合和反应特性， 边缘系统的主要组成部分之一 内在组织 将在家兔中使用高尔基体和变性技术进行评估 个脑袋 快速高尔基体材料将提供有关类型的信息， 神经元及其轴突的皮质内分布，特别是对于 这些细胞是边缘皮层所独有的， 纺锤形金字塔 神经毒素鹅膏蕈氨酸将用于评估 更长的内在连接的密度和范围。 将进行消融 在表层或深层与这种毒素，然后轻， 电子显微镜技术用于确定大多数神经元 在特定层中终止。 毒蕈碱型乙酰胆碱受体 定位于大鼠特定类型的神经元， 用鹅膏蕈氨酸或乙酰乙基胆碱芥末， 使用体外测定的受体密度的变化。 该测定 采用扣带皮层的低温切片，然后孵育 不可逆毒蕈碱配体H3-丙基苄胆碱中的部分 芥末。 还提出了一个彻底的超微结构分析，以 评估到底是什么形态变化的基础行动 兴奋毒素 将在眼部期间评价区域29 d中的神经元反应 动作 急性家兔制备的细胞外记录将 与用红外光监视眼睛位置相结合 安装在接触透镜上的发光二极管。 之间的相位关系 神经元放电与眼的方向、持续时间和幅度 将对移动进行评估。 这些反应的连接基础 将使用丘脑消融和/或皮质冷却进行澄清 除了解剖道追踪技术之外，还可以使用其他技术。 这些项目将使人们更全面地了解 胆碱能系统，因此将有助于解释的变化， 患者的扣带皮层中发生的受体结合模式 患有老年痴呆症 最后，在解释和治疗之前， 的运动障碍运动不能性缄默症可以作出，这将是必要的 来了解扣带皮层的感觉运动功能。

The goals of this investigation are to evaluate the intrinsic organization, receptor binding and response properties of neurons in cingulate cortex, one of the major components of the limbic system. Intrinsic organization will be assessed with Golgi and degeneration techniques in the rabbit brain. Rapid Golgi material will provide information about the types of neurons and the intracortical distribution of their axons, particularly for those cells which are unique to limbic cortex including extraverted and fusiform pyramids. The neurotoxin ibotenic acid will be used to assess the density and extent of longer intrinsic connections. Ablations will be made in the superficial or deep layers with this toxin and then light and electron microscopic techniques used to determine where most of the neurons in a particular layer terminate. Muscarinic acetylcholine receptors will be localized to specific types of neurons in the rat by making ablations with ibotenic acid or acetylethycholine mustard followed by evaluation of changes in the density of receptors using an in vitro assay. This assay employs cryostat sectioning of cingulate cortex followed by incubation of the sections in the irreversible muscarinic ligand H3-propylbenzilylcholine mustard. A thorough ultrastructural analysis is also proposed in order to assess exactly what morphological changes underlie the action of excitotoxins. Neuronal responses will be evaluated in area 29d during eye movements. Extracellular recordings from an acute rabbit preparation will be made in conjunction with monitoring eye position with an infrared light emitting diode mounted on a contact lens. The phase relationships between neuronal discharges and the direction duration and amplitude of eye movements will be evaluated. The connectional basis of these responses will be clarified using thalamic ablation and/or cortical cooling techniques in addition to an anatomical tract tracing technique. These projects will lead to a more complete understanding of the cholinergic system and as such will help to interpret alterations in receptor binding patterns that occur in the cingulate cortices of patients with Alzheimer's disease. Finally, before an interpretation and treatment of the movement disorder akinetic mutism can be made, it will be necessary to understand the sensorimotor functions of cingulate cortex.