van Huijstee Aile N, Kessels Helmut W
Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, the Netherlands; The Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands.
J Neurosci Methods. 2020 Feb 1;331:108526. doi: 10.1016/j.jneumeth.2019.108526. Epub 2019 Nov 19.
The strength of synaptic transmission onto a neuron depends on the number of functional vesicle release sites (N), the probability of vesicle release (P), and the quantal size (Q). Statistical tools based on the quantal model of synaptic transmission can be used to acquire information on which of these parameters is the source of plasticity. However, quantal analysis depends on assumptions that may not be met at central synapses.
We examined the merit of quantal analysis to extract the mechanisms underlying synaptic plasticity by applying binomial statistics on the variance in amplitude of postsynaptic currents evoked at Schaffer collateral-CA1 (Sc-CA1) synapses in mouse hippocampal slices. We extend this analysis by combining the conventional inverse square of the coefficient of variation (1/CV) with the variance-to-mean ratio (VMR).
This method can be used to assess the relative, but not absolute, contribution of N, P and Q to synaptic plasticity. The changes in 1/CV and VMR values correctly reflect experimental modifications of N, P and Q at Sc-CA1 synapses.
While the 1/CV depends on N and P, but is independent of Q, the VMR is dependent on P and Q, but not on N. Combining both allows for a rapid assessment of the mechanism underlying synaptic plasticity without the need for additional electrophysiological experiments.
Combining the 1/CV with the VMR allows for a reliable prediction of the relative contribution of changes in N, P and Q to synaptic plasticity.
神经元上突触传递的强度取决于功能性囊泡释放位点的数量（N）、囊泡释放的概率（P）和量子大小（Q）。基于突触传递量子模型的统计工具可用于获取关于这些参数中哪一个是可塑性来源的信息。然而，量子分析依赖于在中枢突触可能不成立的假设。
我们通过对小鼠海马切片中Schaffer侧支 - CA1（Sc - CA1）突触诱发的突触后电流幅度方差应用二项式统计，研究了量子分析在提取突触可塑性潜在机制方面的价值。我们通过将变异系数的传统倒数平方（1/CV）与方差均值比（VMR）相结合来扩展此分析。
该方法可用于评估N、P和Q对突触可塑性的相对贡献，但不是绝对贡献。1/CV和VMR值的变化正确反映了Sc - CA1突触处N、P和Q的实验性改变。
虽然1/CV取决于N和P，但与Q无关，而VMR取决于P和Q，但不取决于N。将两者结合可快速评估突触可塑性的潜在机制，而无需额外的电生理实验。
将1/CV与VMR结合可可靠预测N、P和Q的变化对突触可塑性的相对贡献。
