Dependence of Generation of Hippocampal CA1 Slow Oscillations on Electrical Synapses

  • Yuan Xu
  • Feng-Yan Shen
  • Yu-Zhang Liu
  • Lidan Wang
  • Ying-Wei Wang
  • Zhiru WangEmail author
Original Article


Neuronal oscillations in the hippocampus are critical for many brain functions including learning and memory. The underlying mechanism of oscillation generation has been extensively investigated in terms of chemical synapses and ion channels. Recently, electrical synapses have also been indicated to play important roles, as reported in various brain areas in vivo and in brain slices. However, this issue remains to be further clarified, including in hippocampal networks. Here, using the completely isolated hippocampus, we investigated in vitro the effect of electrical synapses on slow CA1 oscillations (0.5 Hz–1.5 Hz) generated intrinsically by the hippocampus. We found that these oscillations were totally abolished by bath application of a general blocker of gap junctions (carbenoxolone) or a specific blocker of electrical synapses (mefloquine), as determined by whole-cell recordings in both CA1 pyramidal cells and fast-spiking cells. Our findings indicate that electrical synapses are required for the hippocampal generation of slow CA1 oscillations.


Electrical synapse Hippocampus Oscillation CA1 Mefloquine Carbenoxolone 



This work was supported by grants from the National Natural Science Foundation of China (31471078, 91132711, and 30970960), and a Key Project of Shanghai Science and Technology Commission (15JC1400102 and 19ZR1416600).

Supplementary material

12264_2019_419_MOESM1_ESM.pdf (121 kb)
Supplementary material 1 (PDF 121 kb)


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Copyright information

© Shanghai Institutes for Biological Sciences, CAS 2019

Authors and Affiliations

  • Yuan Xu
    • 1
  • Feng-Yan Shen
    • 2
  • Yu-Zhang Liu
    • 1
  • Lidan Wang
    • 1
  • Ying-Wei Wang
    • 2
  • Zhiru Wang
    • 1
    Email author
  1. 1.Institute and Key Laboratory of Brain Functional Genomics of The Chinese Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life SciencesEast China Normal UniversityShanghaiChina
  2. 2.Department of Anesthesiology, Huashan HospitalFudan UniversityShanghaiChina

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