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Published on: June 5, 2017
Model of concentration changes across the synaptic cleft during a single quantum release.
A I Skorinkin1, A R Shaihutdinova, F Vyskocil
1Institute of Physics, Kazan State University , Kremliovskaja ul. 18, 420008 Kazan, Russia. askorink@yandex.ru
General Physiology and Biophysics
|April 26, 2008
Summary
This study presents a new model for synaptic cleft concentration changes during acetylcholine release. It reveals acetylcholinesterase activity is initially zero, challenging prior assumptions and explaining non-quantal acetylcholine leakage.
Area of Science:
- Neuroscience
- Computational Biology
- Biophysics
Background:
- Synaptic transmission relies on precise neurotransmitter dynamics.
- Acetylcholine (ACh) is a key neurotransmitter, and its hydrolysis by acetylcholinesterase (AChE) is crucial for signal termination.
- Existing models often assume maximal AChE activity at neurotransmitter release, which may not fully explain observed phenomena.
Purpose of the Study:
- To develop a computational model of concentration changes in the synaptic cleft during acetylcholine quantum release.
- To characterize postsynaptic current kinetics influenced by various modulators and blockers.
- To investigate the role and activity profile of acetylcholinesterase (AChE) during synaptic transmission.
Main Methods:
- Development of a mathematical model simulating neurotransmitter concentration dynamics.
- Calculation of the relative number of open postsynaptic channels over time.
- Simulation of two scenarios: active AChE and inhibited AChE.
Main Results:
- The model indicates that the variable component of AChE activity is zero at the moment of ACh release, increasing thereafter.
- This contrasts with the common assumption of maximal initial AChE activity.
- The model explains how non-quantal ACh leakage can evade hydrolysis and reach the subsynaptic membrane.
Conclusions:
- The proposed model offers a novel perspective on AChE activity kinetics during synaptic transmission.
- It provides a framework for understanding the impact of antagonists and modulators on postsynaptic currents.
- The model supports the explanation of non-quantal ACh release mechanisms and their interaction with AChE.
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