Changes of ionic channel distribution in myelinated nerve fibres from rats with experimental allergic neuritis

Voltage clamp experiments were performed in single myelinated nerve fibres of rats with experimental allergic neuritis (EAN). Nerve fibres from diseased animals showed a varying degree of demyelination. In fibres with extensive demyelination large K+ currents were measured. Analysis of the contribution of slow and fast K+ channels revealed that in these fibres the relative contribution of slow K+ channels was about 50% compared to about 25% in fibres acutely demyelinated as previously reported. This indicates that chronic demyelination changes the distinct distribution of ionic channels in the rat node of Ranvier.