DEVELOPMENT OF THE CORTICOTHALAMIC SYSTEM

描述（来自申请人摘要的逐字）：本研究致力于 皮质丘脑系统与躯体感觉区的连接 到丘脑腹后核的神经元。 皮质丘脑纤维的数量远远超过丘脑-皮质投射， 并为整合大脑活动提供了主要途径 大脑皮层和丘脑与意识状态的关系但他们的 发展历史，特别是其在组织 丘脑皮质中身体特异性表征的发展 尚未审查围产期的预测。研究 建议将检查个别皮质丘脑纤维的生长，因为他们 建立它们在丘脑中的分布模式， 大脑皮层本身受到丘脑的支配原则 实验模型为小鼠体外制备。标记群体 将进行轴突生长以建立神经支配的时间模式 以及通过细胞内注射标记单个轴突及其亲本细胞 将建立细胞类型特异性的形态发生序列， 预测。特异性生长因子对皮质丘脑细胞的影响 和轴突的生长。涉及全细胞的生理学方法 体外记录将测量皮质丘脑功能的成熟 以及它与来自皮肤的感官输入通过各种形式的 受体。将识别突触及其相关受体， 使用电子显微镜免疫细胞化学定量。整体 假设皮质丘脑纤维和丘脑之间的相互作用 细胞在建立细颗粒形貌方面是至关重要的， 丘脑皮质神经支配这形成了相互作用的基底 成熟期意识状态变化的基础。是 提出突触分布的发育调节变化， 这些受体对这些细胞的正常成熟至关重要， 交互.缺陷性成熟可能是一个伴随或基础， 年轻人的某些癫痫发作

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.