https://doi.org/10.1351/goldbook.11964
Short interval in the myelin sheath of a nerve fiber where the axon is invested only by scant cytoplasmic processes of the neighboring Schwann cells or, in the central nervous system, of oligodendroglia cells.
Note: At the nodes the axonal membrane is not insulated and contains a high density of voltage-gated \(\ce{Na+}\) channels that generate action potentials.