Differences in action potential propagation speed and axon initial segment plasticity between neurons from Sprague-Dawley rats and C57BL/6 mice

Zhi-Ya Chen; Luxin Peng; Mengdi Zhao; Yu Li; Mochizuki Takahiko; Louis Tao; Peng Zou; Yan Zhang

doi:10.24272/j.issn.2095-8137.2022.121

Volume 43 Issue 4

Jul. 2022

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Article Navigation > Zoological Research > 2022 > 43(4): 615-633

Zhi-Ya Chen, Luxin Peng, Mengdi Zhao, Yu Li, Mochizuki Takahiko, Louis Tao, Peng Zou, Yan Zhang. Differences in action potential propagation speed and axon initial segment plasticity between neurons from Sprague-Dawley rats and C57BL/6 mice. Zoological Research, 2022, 43(4): 615-633. doi: 10.24272/j.issn.2095-8137.2022.121

Citation:

Zhi-Ya Chen, Luxin Peng, Mengdi Zhao, Yu Li, Mochizuki Takahiko, Louis Tao, Peng Zou, Yan Zhang. Differences in action potential propagation speed and axon initial segment plasticity between neurons from Sprague-Dawley rats and C57BL/6 mice. Zoological Research, 2022, 43(4): 615-633. doi: 10.24272/j.issn.2095-8137.2022.121

Citation:

Zhi-Ya Chen, Luxin Peng, Mengdi Zhao, Yu Li, Mochizuki Takahiko, Louis Tao, Peng Zou, Yan Zhang. Differences in action potential propagation speed and axon initial segment plasticity between neurons from Sprague-Dawley rats and C57BL/6 mice. Zoological Research, 2022, 43(4): 615-633. doi: 10.24272/j.issn.2095-8137.2022.121

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Differences in action potential propagation speed and axon initial segment plasticity between neurons from Sprague-Dawley rats and C57BL/6 mice

doi: 10.24272/j.issn.2095-8137.2022.121

Zhi-Ya Chen¹,
Luxin Peng²,
Mengdi Zhao^{3, 7},
Yu Li¹,
Mochizuki Takahiko¹,
Louis Tao^{3, 4
,
,},
Peng Zou^{2, 5, 6, 8
,
,},
Yan Zhang^{1
,
,}

1.
State Key Laboratory of Membrane Biology, College of Life Sciences, Peking University, Beijing 100871, China
2.
College of Chemistry and Molecular Engineering, Synthetic and Functional Biomolecules Center, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Peking University, Beijing 100871, China
3.
Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
4.
Center for Bioinformatics, National Laboratory of Protein Engineering and Plant Genetic Engineering, School of Life Sciences, Peking University, Beijing 100871, China
5.
Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
6.
PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
7.
Beijing Academy of Artificial Intelligence, Beijing 100084, China
8.
Chinese Institute for Brain Research (CIBR), Beijing 102206, China

Funds: This work was supported by the National Science and Technology Innovation 2030-Major Program of “Brain Science and Brain-Like Research” (2022ZD0211800), National Natural Science Foundation of China General Research Grant (81971679, 21727806, 31771147) and Major Research Grant (91632305, 32088101), Ministry of Science and Technology (2018YFA0507600, 2017YFA0503600), Qidong-PKU SLS Innovation Fund (2016000663), and Fundamental Research Funds for the Central Universities and National Key R&D Program of China (2020AAA0105200). P.Z. was sponsored by the Bayer Investigator Award

More Information

Corresponding author: E-mail: taolt@mail.cbi.pku.edu.cn; zoupeng@pku.edu.cn; yanzhang@pku.edu.cn
Received Date: 2022-05-16
Accepted Date: 2022-06-27

Published Online: 2022-06-27

Publish Date: 2022-07-18

Abstract

Abstract

Action potentials (APs) in neurons are generated at the axon initial segment (AIS). AP dynamics, including initiation and propagation, are intimately associated with neuronal excitability and neurotransmitter release kinetics. Most learning and memory studies at the single-neuron level have relied on the use of animal models, most notably rodents. Here, we studied AP initiation and propagation in cultured hippocampal neurons from Sprague-Dawley (SD) rats and C57BL/6 (C57) mice with genetically encoded voltage indicator (GEVI)-based voltage imaging. Our data showed that APs traveled bidirectionally in neurons from both species; forward-propagating APs (fpAPs) had a different speed than backpropagating APs (bpAPs). Additionally, we observed distinct AP propagation characteristics in AISs emerging from the somatic envelope compared to those originating from dendrites. Compared with rat neurons, mouse neurons exhibited higher bpAP speed and lower fpAP speed, more distally located ankyrin G (AnkG) in AISs, and longer Nav1.2 lengths in AISs. Moreover, during AIS plasticity, AnkG and Nav1.2 showed distal shifts in location and shorter lengths of labeled AISs in rat neurons; in mouse neurons, however, they showed a longer AnkG-labeled length and more distal Nav1.2 location. Our findings suggest that hippocampal neurons in SD rats and C57 mice may have different AP propagation speeds, different AnkG and Nav1.2 patterns in the AIS, and different AIS plasticity properties, indicating that comparisons between these species must be carefully considered.
- Sprague-Dawley rats,
- C57BL/6 mice,
- Action potential,
- Axon initial segment,
- Plasticity

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References(80)

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