Following a spinal injury, why does a neuron sometimes fail to propagate an action potential across the damaged region, even if the initial segment depolarizes adequately?

💡 Explanation

Demyelination increases membrane capacitance because it exposes the axonal membrane, therefore increasing the charge needed to change the membrane potential. This prevents the action potential from regenerating efficiently across the demyelinated region, rather than astrocyte glutamate uptake or cytokine secretion directly blocking propagation.

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