SYNAPTIC ORGANIZATION OF BASAL FOREBRAIN PROJECTIONS

这项研究的目的是提供生理和 神经通路突触组织的药理学分析 从大鼠基底前脑到边缘系统和丘脑， 从边缘系统到基底的相互投射 前脑 首先，传出投射的生理学研究 将继续进行大鼠基底前脑的研究。 工作将 集中于从斜角带核的投射 Broca，无名质和邻近的基底前脑， 丘脑背内侧核和网状核。 为了实现 为了达到这个目的，基底前脑会受到刺激， 电，突触电位对此作出反应， 刺激将在丘脑的细胞内被记录。 通过细胞内HRP注射鉴定靶细胞。 其次，将进行药理学分析，研究 从基底前脑到边缘系统的假定胆碱能投射 皮质（特别是内嗅皮质，下托复合体， 扣带皮层）;和丘脑（特别是内嗅皮层， 下托复合体和扣带皮层）;和丘脑 （特别是中间背核和网状核）。 是 假设目标主细胞是通过慢- 作用M1毒蕈碱受体。 胆碱能激动剂和 拮抗剂将在电刺激期间通过离子电渗法应用， 刺激基底前脑 刺激的效果将 与胆碱能激动剂的作用相比， 胆碱能拮抗剂阻断诱发的 将确定突触。 第三，神经元核投射的生理作用。 将确定来自下托复合体的对角线带。 由于这种投射的生理作用是未知的， 体内细胞内记录实验将是有价值的， 建立边缘皮层在对角线上的突触作用 带状神经元 这些细胞内和药理学研究解决了 最好在系统层面上进行研究， 体内制备 基底前脑的胆碱能细胞， 他们的边缘系统目标似乎在老年痴呆症中经历了退化 疾病 因此，对这种神经系统的了解可以 提供与此相关的精神病理学的见解 疾病

The objectives of this research are to provide physiological and pharmacological analyses of the synaptic organization of pathways from the rat basal forebrain to the limbic system and thalamus, and reciprocal projections from the limbic system to the basal forebrain. First, physiological studies of efferent projections from the rat basal forebrain will be continued. Work will concentrate on projections from the nucleus of the diagonal band of Broca, substantia innominata, and adjacent basal forebrain to the thalamic mediodorsal and reticular nuclei. In order to achieve this objective, the basal forebrain will be stimulated electrically, and synaptic potentials in response to this stimulation will be recorded intracellularly in the thalamus. Target cells will be identified by intracellular HRP injection. Second, a pharmacological analysis will be performed, studying putative cholinergic projections from the basal forebrain to limbic cortex (specifically entorhinal cortex, subicular complex, and cingulate cortex); and thalamus (specifically entorhinal cortex, subicular complex, and cingulate cortex); and thalamus (specifically the mediodorsal and reticular nuclei). It is hypothesized that target principal cells are excited via slow- acting M1 muscarinic receptors. Cholinergic agonists and antagonists will be iontophoretically applied during electrical stimulation of the basal forebrain. The effect of stimulation will be compared to the action of the cholinergic agonists, and the efficacy of the cholinergic antagonists in blocking the evoked synaptic will be determined. Third, the physiological action of projections to the nucleus of the diagonal band from the subicular complex will be determined. Since the physiological action of this projection is unknown, in vivo intracellular recording experiments will be valuable in establishing the synaptic action of the limbic cortex on diagonal band neurons. These intracellular and pharmacological studies attack problems that can best be studied at the systems level in the intact, in vivo preparation. The cholinergic cell of the basal forebrain, and their limbic targets appear to undergo degeneration in Alzheimer's disease. An understanding of this neuronal system can therefore provide insight into the psychopathology associated with this disease.