Analysis of high-frequency stimulation-evoked synaptic plasticity in mouse hippocampal CA1 region.
Extracellular recordings of field excitatory postsynaptic potential (fEPSP) is one of the most common ways for studies of synaptic plasticity, such as long-term potentiation (LTP) and paired-pulse plasticity (PPP). The measurement of the changes in the different components of fEPSP waveform, such as the initial slope, initial area, peak amplitude and whole area, were commonly used as criteria for the judgement of potentiation or depression of synaptic plasticity. However, the differences in the conclusions drawn from measuring different components of fEPSP waveform at the same recording have still been largely ignored. Here we compared high-frequency stimulation (HFS)-evoked synaptic plasticity, both LTP and PPP, by measuring different components of fEPSP waveform, including the initial slope, initial area, peak amplitude, whole area and time course. The results not only indicated the acceleration of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor kinetics underlies LTP in hippocampal CA1 region of mice, but also showed that different measurements of fEPSP waveform at the same recording result in different magnitudes of LTP and different forms of PPP in hippocampal CA1 region of mice. After HFS, the paired-pulse ratio was slightly decreased by measurement of the initial area, but obviously increased by measurement of the initial slope of the pair fEPSPs. These results might draw apparently contradictory conclusions. Therefore, careful and complete analysis of the data from different parts of fEPSP waveforms is important for reflection of the faithful changes in synaptic plasticity.
Liu
Xi-Juan
XJ
Department of Physiology and Pathophysiology, Medical School of Xi'an Jiaotong University, Xi'an 710061, China.
Huang
Fen-Sheng
FS
Huang
Chen
C
Yang
Zhang-Min
ZM
Feng
Xin-Zheng
XZ
D000818:Animals; D056547:CA1 Region, Hippocampal / Q000502:physiology*; D019706:Excitatory Postsynaptic Potentials; D017774:Long-Term Potentiation; D051379:Mice; D009473:Neuronal Plasticity; D018091:Receptors, AMPA / Q000378:metabolism
D018091:Receptors, AMPA