Effects of single- and hybrid-frequency extremely low-frequency electromagnetic field stimulations on long-term potentiation in the hippocampal Schaffer collateral pathway

Abstract

Purpose: To study the different effects of single- and hybrid-frequency magnetic fields on long-term potentiation (LTP) in synaptic plasticity.

Materials and methods: Based on the online electromagnetic field stimulation system and field excitatory postsynaptic potentials (fEPSPs) recording system, we applied four different single- and hybrid-frequency magnetic fields with an intensity of 1 mT to the Schaffer collateral (CA1) pathway of rat hippocampal slices in vitro.

Results: The amplitude of fEPSPs decreased significantly under both single- and hybrid-frequency magnetic stimulation. Lower single-frequency magnetic stimulation on LTP had a greater regulating effect, while the regulating effect among four different hybrid-frequency extremely low-frequency electromagnetic fields (ELF-EMFs) stimulations on LTP showed no significant differences.

Conclusion: Single-frequency magnetic stimulation produces more significant regulatory effects, and the lower the frequency, the more significant the regulatory effect. The effect of hybrid-frequency magnetic stimulation in each group was similar, and there was no significant difference between each group. The 15-Hz single-frequency magnetic stimulation group showed the most significant regulatory effect, but once it was mixed with other higher frequency magnetic stimulation, its regulation effect was significantly weakened.

Keywords:

• Extremely low-frequency electromagnetic fields (ELF-EMFs)
• hybrid-frequency
• long-term potentiation (LTP)
• single-frequency
• Schaffer collaterals pathway

Disclosure statement

The authors report no conflicts of interest.

Additional information

Funding

This work was supported by grants from the National Natural Science Foundation of China [61871288].

Notes on contributors

Yu Zheng

Yu Zheng is an Associate professor of Biomedical engineering in the School of Electronics and Information Engineering, Institute of Tianjin Polytechnic University. His research interests are in mechanisms of low frequency bioelectromagnetic radiation on synaptic plasticity.

Xiao-xu Ma

Xiao-xu Ma is a graduate student of Biomedical engineering in the School of Electronics and Information Engineering, Institute of Tianjin Polytechnic University.

Lei Dong

Lei Dong is now studying for PhD degree of instrumentation science and technology in the School of Laboratory of Precision Measurement Technology and Instruments, Institute of Tianjin University.

Yang Gao

Yang Gao is now studying for PhD degree of Biomedical Imaging in The School of Information Technology and Electrical Engineering, The University of Queensland. His research interest now is mainly medical image and data processing.

Lei Tian

Lei Tian is a Research Assistant Professor of Biomedical engineering in the School of Electronics and Information Engineering, Institute of Tianjin polytechnic University.