Potassium channel modulation – a therapeutic principle? 4-Aminopyridine in autoimmune central nervous system disease

4-Aminopyridine (4-AP) is a potassium channel blocking agent. Electrophysiologic studies of demyelinated axons have shown that augmented potassium currents increase extracellular potassium ion concentrations which decrease action potential duration and amplitude which may cause conduction failure. Potassium channel blockade might reverse this effect and could therefore be neuroprotective in autoimmune disorders of the central nervous system like Multiple Sclerosis (MS). To test this hypothesis, we studied the effects of 4-AP in the animal model of MS, the experimental autoimmune encephalomyelitis (EAE). 4-AP was…