PLOS BiologyApr 25, 2025
Are action potentials in vertebrate muscle essential for contraction? This study of #zebrafish lacking #SodiumChannel NaV1.4 reveals that NaVs are dispensable for #muscle contraction, so the need for muscle #ActionPotentials can vary between vertebrates @PLOSBiology https://plos.io/42EXQwx
Normal locomotion in zebrafish lacking the sodium channel NaV1.4 suggests that the need for muscle action potentials is not universal

It is widely accepted that action potentials in vertebrate muscle are indispensable for contraction. This study of zebrafish lacking the sodium channel NaV1.4 reveals that NaVs are not essential for muscle contraction, and that the physiological requirement for action potentials in muscle can vary between vertebrates.

PLOS BiologyDec 4, 2024
Why is neuronal repolarization during #ActionPotentials so uniform despite ~10x range in axonal diameter? Study shows that higher K+ currents in smaller #axons compensate for biophys constraints, resulting in size-independent trigger signals #PLOSBiology https://plos.io/3ZzJvzE
Axons compensate for biophysical constraints of variable size to uniformize their action potentials

Why is the repolarization phase of the neuronal actional potential so uniform despite the variability in axon diameters? This study shows that increased Kv1 potassium currents in smaller axonal structures compensate for their biophysical constraints resulting in size-independent synaptic trigger signals along the entire axon.