CALCIUM MEDIATED EXOCYTOSIS OF NEUROTRANSMITTER DURING SYNAPTIC TRANSMISSION

突触传递过程中钙介导的神经递质胞吐作用

• 批准号: 6220678
• 负责人: WILLIAM M ROBERTS
• 金额: $ 5.77万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-05-15 至 2000-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6220678
• 关键词: Mammalia; biomedical resource; cognition; human tissue; informatics; microscopy; model design /development; nervous system; taste; technology /technique

Although the correlation between synaptic structure and function has been studied in detail at the neuromuscular junction, we face many open questions. Central synapses are even less well understood. Recent studies have shown that the size of a single synaptic contact is correlated to its function. In particular the number of vesicles docked at the active zone seems to accurately predict the release probability of that contact. It is not clear, however, whether every vesicle contributes equally to the release probability. An exact mapping of the position of docked vesicles might reveal functional differences between individual vesicles. We, therefore, reconstructed hippocampal synapses by using high voltage electron microscopy and tomographic 3-D reconstructions. Using this method we can resolve the position of every vesicle with an error of less than 10 nm in all dimensions, whereas reconstructions from serial sections are limited to a 6 times lower resolution in the z-axis. Thus far, 10 synapses have been reconstructed. The center to center distances of the docked vesicles were calculated using the program xdsphere developed at NCMIR by Stephan Lamont and analyzed with the pair correlation function. The function shows a complex but orderly pattern that is consistent between active zones. This work was presented at the Winter Brain Conference this year in Park City, Utah.

虽然突触结构和功能之间的相关性 已经在神经肌肉接头详细研究，我们面临许多 开放性问题。 中央突触更不为人所知。 最近的研究表明单个突触接触的大小 与其功能相关。 特别是囊泡的数量 停靠在活动区似乎可以准确地预测 这种接触的可能性。 然而，目前尚不清楚是否所有 囊泡对释放概率的贡献相等。 一个确切 对接囊泡的位置映射可能揭示功能性 个体囊泡之间的差异。 因此，我们重建了 海马突触的高压电镜观察， 断层扫描三维重建 使用这种方法，我们可以解决 每个囊泡的位置误差总体小于10纳米 尺寸，而连续切片的重建是有限的 在z轴上的分辨率低6倍。 到目前为止， 已经被重建。 停靠的中心到中心距离 使用NCMIR开发的程序xdsphere计算囊泡 由Stephan拉蒙提出，并用对相关函数进行了分析。 该函数显示了一种复杂但有序的模式， 活动区域之间。 这项工作是在冬季大脑 今年的会议在犹他州帕克城举行。