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Updated: Jul 14, 2026
08:13
Simultaneous Pre- and Post-synaptic Electrophysiological Recording from Xenopus Nerve-muscle Co-cultures
Published on: March 11, 2013
Schwann cell-derived factors modulate synaptic activities at developing neuromuscular synapses.
1Section of Neurobiology, Department of Biological Sciences, University of Southern California, Los Angeles, California 90089-2520, USA.
Summary
Schwann cells release small molecules that significantly boost spontaneous neurotransmission at developing neuromuscular junctions. This glial cell activity, involving calcium influx, enhances synaptic development and function.
Area of Science:
- Neuroscience
- Cell Biology
- Synaptic Plasticity
Background:
- Glial cells, specifically Schwann cells, play crucial roles in synapse formation, function, and maintenance.
- Understanding neuron-glia interactions is key to deciphering synaptic development and plasticity.
Purpose of the Study:
- To investigate how Schwann cell-derived factors modulate synaptic function at developing neuromuscular junctions (NMJs).
- To identify the molecular characteristics of these factors and their effects on synaptic transmission.
Main Methods:
- Application of Xenopus Schwann cell-conditioned medium (SC-CM) to developing Xenopus nerve-muscle cocultures and tadpoles.
- Measurement of spontaneous synaptic currents (SSCs) and evoked transmitter release.
- Utilized molecular weight cutoff filters and dialysis membranes to characterize functional factors.
Main Results:
- SC-CM acutely increased spontaneous synaptic current frequency by ~150-fold at developing NMJs.
- This effect was presynaptic, calcium-dependent, and required the motoneuron soma.
- SC-CM suppressed evoked transmitter release and was not due to known factors like neurotrophins, glutamate, or ATP.
Conclusions:
- Schwann cells release small molecules (500-5000 Da) that potently enhance spontaneous neurotransmission at developing NMJs.
- This glial-mediated enhancement of spontaneous activity may play a significant role in synaptogenesis.
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