Development and Plasticity of a Retinotectal System

视网膜顶盖系统的发育和可塑性

• 批准号: 6674519
• 负责人: MU-MING POO
• 金额: $ 36.17万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6674519
• 关键词: Xenopus; cell morphology; electronic recording system; electrophysiology; evoked potentials; long term potentiation; neural plasticity; neurophysiology; retina; retinal ganglion; superior colliculus; synaptogenesis; visual fields; visual pathways; visual photoreceptor

DESCRIPTION (provided by applicant): In the developing visual system, the spatiotemporal patterns of visual inputs play an important role in shaping the connections of developing circuits. Using the developing retinotectal system of Xenopus tadpoles and a combination of in vivo whole cell recording and optical imaging techniques, we proposed to examine the development and experience-dependent refinement of visual circuits at the cellular level. In particular, we will examine the potential link between activity-dependent persistent synaptic modifications known as long-term potentiation/depression (LTP/LTD) and developmental refinement of visual circuits. The proposal consists of four parts. In PART I, we will examine the time course of synaptogenesis in the tectum, developmental changes in the synaptic function and plasticity and in the receptive field properties of tectal neurons, using a whole-cell recording method that allows the selective assessment of changes in glutamatergic and GABAergic/glycinergic inputs to the tectal neuron. The modulatory influence of GABAergic/glycinergic inputs on the development of receptive field properties will also be studied. In PART II, we will examine the effects of visual experience-evoked activity on retinotectal synapses and on the development of retinotopic map and receptive field properties. We will also determine the role of spike-timing dependent plasticity in the activity-induced refinement of retinotectal connections. In PART III, we will examine the relationship between activity-induced LTP/LTD and the structural refinement at identified retinotectal connections and the role of cooperative and competitive interactions among converging retinal inputs on the dendrite of single tectal neurons. Finally, in PART IV, we will examine the process by which visual input-induced LTP/LTD and structural modifications of retinotectal connections can be consolidated and become resistant to disruption by subsequent spontaneous spiking activity in the retinotectal system. Taken together, these in vivo studies provide unique opportunities to address several fundamental issues concerning the instructive function of sensory inputs in the refinement of developing neural connections, and are likely to yield new information relevant to our basic understanding of physiology and pathology of the developing nervous system.

描述（由申请人提供）：在开发的视觉系统中，视觉输入的时空模式在塑造发展电路的连接方面起着重要作用。我们使用开发的爪蟾t骨的视网膜直肠直肠系统以及体内整体记录和光学成像技术的组合，我们提议研究细胞水平上视觉电路的发展和经验依赖性的细化。特别是，我们将研究称为长期增强/抑郁症（LTP/LTD）的活动依赖性持续的突触修饰与视觉电路的发展之间的潜在联系。该提案由四个部分组成。在第一部分中，我们将使用一种全细胞记录方法来检查构件中突触发生的时间过程，突触功能和可塑性的发育变化以及张力直肠神经元的接受场特性的变化，允许对谷氨酸甲基甲基甲基甲基甲基和GABAERGIC和GABAERGIC和GLUTAMEGIC/GLYCINEGIC/GLYCINEGIC输入的变化进行选择的评估。还将研究GABA能/糖能输入对接受场特性发展的调节作用。在第二部分中，我们将研究视觉经验诱发的活动对视网膜直肠突触以及视网膜图和接受场特性的发展的影响。我们还将确定依赖性可塑性在活动引起的视网膜直肠连接的完善中的作用。在第三部分中，我们将研究活性诱导的LTP/LTD与确定的视网膜直肠连接处的结构改进之间的关系，以及在单个侧直肠神经元的树突上收敛的视网膜输入之间合作和竞争性相互作用的作用。最后，在第四部分中，我们将研究视觉输入诱导的LTP/LTD和视网膜直肠连接的结构修饰的过程，可以合并，并通过随后的视网膜直肠系统中的自发尖峰活动来抗性。综上所述，这些体内研究提供了独特的机会，可以解决有关感官投入在发展神经联系中的启发性功能的几个基本问​​题，并且很可能会产生与我们对发展神经系统生理学和病理学的基本理解有关的新信息。