AUTHOR=Taylor Henry B. C. , Tong Rudi , Jeans Alexander F. , Emptage Nigel J. 

TITLE=A Novel Optical Quantal Analysis of Miniature Events Reveals Enhanced Frequency Following Amyloid β Exposure

JOURNAL=Frontiers in Cellular Neuroscience

VOLUME=Volume 14 - 2020

YEAR=2020

URL=https://www.frontiersin.org/journals/cellular-neuroscience/articles/10.3389/fncel.2020.564081

DOI=10.3389/fncel.2020.564081

ISSN=1662-5102

ABSTRACT=Non-evoked miniature release of neurotransmitter is increasingly recognised as playing an important role in neural function, and is implicated in synaptic plasticity, metaplasticity, and homeostasis. Spontaneous miniature release events (minis) are usually measured electrophysiologically by recording the miniature postsynaptic currents (mEPSCs) that they evoke. However, this indirect technique can be confounded by changes within the postsynaptic neuron. Here, using the fluorescent probe SynaptopHluorin 2x, we have developed an optical method for the measurement of minis that enables direct assessment of release events. We use the technique to reveal that the frequency of minis following incubation of hippocampal neurons with Amyloid  oligomers (Ao) is increased. This contrasts with electrophysiological mEPSC data that reports a decrease in frequency under the same conditions, likely arising from changes occurring in the postsynaptic neuron. Optical quantal analysis of minis can help us to understand the important role that minis play in both normal physiology and disease and can help unmask effects obscured by postsynaptic changes.