NEUROTRANSMITTER RECEPTOR DYNAMICS IN VIVO

神经递质受体体内动力学

• 批准号: 6591230
• 负责人: MOHAMMED AKAABOUNE
• 金额: $ 5.21万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-03-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6591230
• 关键词: acetylcholine; action potentials; calcium channel blockers; cholinergic receptors; genetically modified animals; immunocytochemistry; laboratory mouse; neuromuscular blocking agents; neuromuscular junction; neuromuscular transmission; neuropharmacology; receptor expression; tetrodotoxin

The main objective of this project is to better understand how neurotransmitter receptor aggregations are regulated and maintained at a synapse. Newly developed techniques for monitoring changes in the number of acetylcholine receptors at individual neuromuscular junctions in living mice will be used. This approach permits quantification of the rates of receptor addition and loss from an identified synapse over periods of minutes to months. Modifications of the activity of the neuromuscular synapse will be used to analyze the role of postsynaptic activity in modulating receptor numbers. The use of high resolution confocal microscopy fluoresce recovery after photobleaching, and two color receptor labeling, will help resolve whether newly synthesized receptors are added directly to the junction or are inserted into the perijunctional region and then migrate to the junction where they are trapped. Lastly, these experiments will examine the consequences of long-term blockade of neuromuscular transmission on the subsequent function of the neuromuscular junction. This question is clinically important because patients who have been treated with neuromuscular blocking agents for several days occasionally remain paralyzed for weeks after removing the blocking agents. The etiology of this devastating syndrome is not known but seems analogous to the effects of neuromuscular blockade observed in the preliminary work that supports this application. Because activity and inactivity induced changes in receptor numbers are thought to be instrumental in long-term potentiation and depression in the central nervous system, the studies proposed here may provide fundamental information concerning the effects of activity on synaptic strength at less accessible synapses.

该项目的主要目标是更好地了解神经递质受体聚集如何在突触处调节和维持。 将使用新开发的技术来监测活体小鼠个体神经肌肉接头处乙酰胆碱受体数量的变化。这种方法可以量化在几分钟到几个月的时间内从已识别的突触中受体添加和丢失的速率。 神经肌肉突触活动的修饰将用于分析突触后活动在调节受体数量中的作用。 使用光漂白后的高分辨率共焦显微镜荧光恢复和两种颜色受体标记，将有助于解决新合成的受体是直接添加到连接处还是插入到连接处周围区域，然后迁移到它们被捕获的连接处。 最后，这些实验将检查长期阻断神经肌肉传递对神经肌肉接头后续功能的影响。 这个问题在临床上很重要，因为接受神经肌肉阻断剂治疗数天的患者有时在去除阻断剂后仍会瘫痪数周。这种破坏性综合症的病因尚不清楚，但似乎与支持该应用的初步工作中观察到的神经肌肉阻滞的影响类似。 由于活动和不活动引起的受体数量变化被认为有助于中枢神经系统的长期增强和抑制，因此本文提出的研究可能提供有关活动对不易接近的突触处的突触强度的影响的基本信息。