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GABA receptors near sodium channels facilitate spike propagation in myelinated axons

Although axonal GABAA receptors are thought to cause presynaptic inhibition, we show that instead they often facilitate sodium channel activation at nodes of myelinated axons. This facilitation determines which branches of sensory axons conduct action potentials to motor neurons, enabling computation at the level of the node to regulate sensory feedback.

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Fig. 1: Graphical summary of nodal facilitation.

References

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This is a summary of: Hari, K. et al. GABA facilitates spike propagation through branch points of sensory axons in the spinal cord. Nat. Neurosci. https://doi.org/10.1038/s41593-022-01162-x (2022).

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GABA receptors near sodium channels facilitate spike propagation in myelinated axons. Nat Neurosci 25, 1253–1254 (2022). https://doi.org/10.1038/s41593-022-01163-w

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