DEVELOPMENT OF THE CORTICOTHALAMIC SYSTEM

描述(逐字摘自申请人的摘要)：这项研究致力于 参与躯体感觉区的皮质丘脑系统的发育 从大脑皮层到丘脑腹侧后核。 皮质丘脑纤维的数量远远超过丘脑皮质投射的纤维数量， 为整合大脑活动提供了主要途径 大脑皮质和丘脑与意识状态的关系。然而，他们的 发展历史，特别是它们在组织 丘脑皮质中身体特异性表征的研究进展 围产期的投射没有被检查过。这项研究 将研究单个皮质丘脑纤维的生长情况 在此期间，建立它们在丘脑的分布模式 当大脑皮质本身受到丘脑的支配时。原则性 实验模型为小鼠体外制备。白纹伊蚊种群的标记 将进行轴突生长以建立神经支配的时间模式 通过细胞内注射对单个轴突及其亲本细胞进行标记 将建立细胞类型特异性的形态发生序列 投射。特异性生长因子对皮质丘脑细胞的影响 并将检查轴突生长情况。涉及全细胞的生理学方法 在体外，记录将测量皮质丘脑功能的成熟程度 以及它与来自皮肤的感觉输入之间的相互作用 感受器。突触及其相关受体将被识别并 用电子显微镜免疫细胞化学方法进行定量。整体而言 假设皮质丘脑纤维和丘脑之间的相互作用 细胞在建立细粒形貌特征方面是至关重要的 丘脑皮质神经支配。这形成了相互作用的底物 丘脑和大脑皮层是成熟期意识状态变化的基础。它是 提出了发育调节的突触分布变化和 参与的受体对这些细胞的正常成熟至关重要。 互动。有缺陷的成熟可能是伴随的或基础的 年轻人的某些形式的癫痫发作。

DESCRIPTION (Verbatim from the Applicant's Abstract): This research is devoted to the development of the corticothalamic system joining the somatosensory area of the cerebral cortex to the ventral posterior nucleus of the thalamus. Corticothalamic fibers far outnumber those of the thalamo-cortical projection, and provide the main pathway for integrating the activities of the cerebral cortex and thalamus in relation to the state of consciousness. However, their developmental history and especially their potential role in organizing the development of the body-specific representation in the thalamocortical projection during the perinatal period has not been examined. The research proposed will examine the growth of individual corticothalamic fibers as they establish their patterns of distribution in the thalamus, during the period when the cortex is itself being innervated by the thalamus. The principle experimental model is a mouse in vitro preparation. Labeling of populations of growing axons will be carried out to establish temporal patterns of innervation and labeling of single axons and their parent cells by intracellular injections of dyes will establish the morphogenetic sequence of cell-type specific projections. The influence of specific growth factors on corticothalamic cell and axon growth will be examined. Physiological methods involving whole cell recording, in vitro, will measure the maturation of corticothalamic function and its interactions with sensory inputs from the skin via various forms of receptors. The synapses and their associated receptors will be identified and quantified using electron microscopic immunocytochemistry. The overall hypothesis is that interactions between corticothalamic fibers and thalamic cells are critical in establishing the fine grain topography that characterizes thalamocortical innervation. This forms a substrate for interactions between thalamus and cortex that underlie changes in conscious state in maturity. It is proposed that developmentally regulated changes in synaptic distribution and the receptors engaged are critical to the normal maturation of these interactions. Defective maturation may be a concomitant of or a basis for certain forms of seizures in young individuals.