期刊
JOURNAL OF NEUROSCIENCE
卷 28, 期 8, 页码 1894-1903出版社
SOC NEUROSCIENCE
DOI: 10.1523/JNEUROSCI.4518-07.2008
关键词
presynaptic terminal; quantal release; fluorescence microscopy; vesicle transport; kiss-and-run; hippocampus
资金
- NIMH NIH HHS [R01 MH060600, MH60600] Funding Source: Medline
In small presynaptic boutons in brain, synaptic vesicles are thought not to merge with the plasma membrane when they release transmitter, but instead to close their fusion pores and survive intact for future use ( kiss-and-run exocytosis). The strongest evidence for this idea is the slow and incomplete release of the fluorescent membrane marker, FM1-43 [N-(3-triethylammoniumpropyl)-4-(4-(dibutylamino) styryl) pyridinium dibromide], from single vesicles. We investigated the release of FM1-43 from sparse cultures of hippocampal neurons grown on coverslips with no glia. This allowed presynaptic boutons to be imaged at favorable signal-to-noise ratio. Sparingly stained boutons were imaged at high time resolution, while high-frequency electrical stimulation caused exocytosis. The release of FM1-43 was quantal and occurred in abrupt steps, each representing a single fusion event. The fluorescence of vesicle clusters traveling along axons had a distribution with the same quantal size, indicating that a vesicle releases all the dye it contains. In most fusion events, the time constant of dye release was < 100 ms, and slower release was rarely observed. After exocytosis, no FM1-43 could be detected in the axon to either side of a bouton, indicating that dye was released before it could spread. Our results are consistent with synaptic vesicles fusing fully with the plasma membrane during high-frequency stimulation.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据