Related Experiment Video
Updated: Jul 4, 2026
08:31
FM Dye Cycling at the Synapse: Comparing High Potassium Depolarization, Electrical and Channelrhodopsin Stimulation
Published on: May 24, 2018
[Vesicle cycle in mouse diaphragm motor nerve terminals]
Summary
Mouse motor nerve terminals maintain high-frequency activity through rapid synaptic vesicle recycling. This process involves fast endocytosis and reuse, ensuring effective neurotransmission during prolonged stimulation.
Area of Science:
- Neuroscience
- Cell Biology
- Physiology
Context:
- Investigating neurotransmitter secretion and synaptic vesicle recycling dynamics.
- Utilizing mouse diaphragm muscles under long-term rhythmic stimulation (20Hz).
- Employing intracellular microelectrode registration and fluorescent microscopy.
Purpose:
- To explore the exo-endocytosis cycle of synaptic vesicles during sustained high-frequency nerve activity.
- To quantify the sizes of ready releasable and recycling synaptic vesicle pools.
- To determine the rate of synaptic vesicle reuse and its impact on synaptic transmission.
Summary:
- Rhythmic stimulation induced a three-phase change in end-plate potential amplitude: initial decrease, plateau, and secondary decrease.
- Fluorescent dye FM 1-43 revealed gradual fluorescence decrease, indicating synaptic vesicle exocytosis.
- Electrophysiological and fluorescent data suggest a high rate of endocytosis and rapid vesicle reuse (approx. 50 sec recycling time).
Impact:
- Demonstrates efficient synaptic transmission maintenance during prolonged high-frequency activity in mouse motor nerve terminals.
- Quantifies synaptic vesicle pools and suggests a fast recycling pathway.
- Highlights the repeated cycling of recycling pool vesicles without engaging the reserve pool under the tested conditions.
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