Readily releasable pool of synaptic vesicles measured at single synaptic contacts.
Readily releasable pool of synaptic vesicles measured at single synaptic contacts.
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在单个突触接触处测量的易于释放的突触小泡池。
DOI：
10.1073/pnas.1209798109
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Marty A
中科院分区：
文献类型：
--
作者：
Trigo FF;Sakaba T;Ogden D;Marty A
为了区分脑突触中不同的囊泡释放模式，有必要知道在高钙刺激下，单个突触可以立即释放的递质囊泡的数量，即易释放池(RRP)。我们在已识别的单部位抑制性突触上用去钙直接刺激来研究囊泡释放的统计和RRP的大小。在突触后神经元中被检测为量子反应的囊泡释放，显示出在高细胞内钙刺激下，从刺激到刺激的量子数目意外的随机变化，平均每个刺激1.9个，最多3到4个。结果提供了在单个突触位置的RRP的直接测量。它们与释放来自少量囊泡对接位置的模型是一致的，平均占有率约为0.7。
To distinguish between different models of vesicular release in brain synapses, it is necessary to know the number of vesicles of transmitter that can be released immediately at individual synapses by a high-calcium stimulus, the readily releasable pool (RRP). We used direct stimulation by calcium uncaging at identified, single-site inhibitory synapses to investigate the statistics of vesicular release and the size of the RRP. Vesicular release, detected as quantal responses in the postsynaptic neuron, showed an unexpected stochastic variation in the number of quanta from stimulus to stimulus at high intracellular calcium, with a mean of 1.9 per stimulus and a maximum of three or four. The results provide direct measurement of the RRP at single synaptic sites. They are consistent with models in which release proceeds from a small number of vesicle docking sites with an average occupancy around 0.7.