Estimating transmitter release rates and quantal amplitudes in central synapses from postsynaptic current fluctuations.
Estimating transmitter release rates and quantal amplitudes in central synapses from postsynaptic current fluctuations.
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发表时间：
2004
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通讯作者：
A. Stepanyuk;Y. Boychuk;T. N. Tsugorka;Y. Drebot;I. Lushnikova;T. Pivneva;P. Belan
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作者：
A. Stepanyuk;Y. Boychuk;T. N. Tsugorka;Y. Drebot;I. Lushnikova;T. Pivneva;P. Belan
然而，最近引入的几种分析中枢突触释放速率的方法推进了我们对突触神经传递的理解，留下了许多尚未解决的问题。在这项工作中，我们提出的证据表明，一种新的方法最近开发的Sakaba和Neher研究的神经传递在花萼举行，一个巨大的神经元突触，也可以应用于估计释放率函数和平均量子尺寸在小的中央突触。通过应用不同的模拟方法来再现海马中GABA能神经传递，我们已经表明，当突触紧密分布或位于近端且释放速率低于1 ms（-1）时，可能发生在分布在大面积树突树上的突触连接中的空间电压钳的可能问题对于该方法的适用性不是至关重要的。在另一组模拟中，我们还表明，在上述释放速率下，突触后GABAA受体的脱敏和/或饱和并不妨碍对释放速率和平均量子大小的准确估计。因此，我们的结论是，新的方法的基础上分析的突触后电流的波动条件下的固定释放或中度非固定条件下可能适用于小的中央突触的研究。
Several approaches recently introduced to analyze release rates in central synapses advanced our understanding of synaptic neurotransmission, however, leaving many questions still unresolved. In this work we present evidence that a new method recently developed by Sakaba and Neher to study neurotransmission in calyx of Held, a giant glutamatergic synapse, could be also applied for estimating release rate functions and averaged quantal sizes in small central synapses. By means of different simulation approaches applied to reproduce GABAergic neurotransmission in the hippocampus we have shown that possible problems with a spatial voltage clamp which can occur in synaptic connections distributed over a large area of dendritic tree are not crucial for applicability of the method when synapses are compactly distributed or located proximally and when release rates are below 1 ms(-1). In another set of simulations we have also shown that at above mentioned release rates desensitization and/or saturation of postsynaptic GABAA receptors does not prevent accurate estimates of release rate and averaged quantal size. Thus, we conclude that the new approach based on analysis of fluctuations of postsynaptic currents under conditions of stationary release or moderately nonstationary conditions might be applicable to studies of small central synapses.