Related Experiment Video
Updated: Jun 9, 2025
07:40
Measuring Properties of the Membrane Periodic Skeleton of the Axon Initial Segment using 3D-Structured Illumination Microscopy 3D-SIM
Published on: February 11, 2022
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Axon initial segment structure and function in health and disease.
Paul M Jenkins1, Kevin J Bender2
1Departments of Pharmacology and Psychiatry, University of Michigan Medical School, Ann Arbor, Michigan, United States.
Physiological Reviews
|October 31, 2024
Summary
The axon initial segment (AIS) integrates synaptic inputs to generate action potentials (APs). This review covers recent advances in understanding the AIS
Area of Science:
- Neuroscience
- Cell Biology
- Computational Biology
Background:
- Neurons process synaptic inputs into action potentials (APs) at the axon initial segment (AIS).
- The AIS is a specialized neuronal compartment rich in proteins and organelles, crucial for neuronal function.
- Its roles in regulating excitability and maintaining neuronal polarity are critical in health and disease.
Purpose of the Study:
- To review recent advancements in the understanding of the axon initial segment (AIS).
- To elucidate the AIS's role in neuronal integration and polarity.
- To discuss the implications of AIS function in both healthy and diseased states.
Main Methods:
- Literature review of experimental and theoretical studies.
- Synthesis of recent findings on AIS structure and function.
- Analysis of AIS contribution to neuronal excitability and compartmentalization.
Main Results:
- The AIS acts as a critical site for action potential initiation.
- It functions as a gatekeeper, separating somatodendritic and axonal domains.
- Dynamic regulation of AIS properties influences neuronal excitability and integration.
Conclusions:
- The AIS is a key regulator of neuronal excitability and integration.
- Understanding AIS function is vital for comprehending neuronal polarity.
- Advances in AIS research offer insights into neurological disorders.
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