Recent studies have shown that the acid-sensing ion channel 1 (ASIC1) contributes to the axonal degeneration in CNS lesions Physiologically, ASIC1 has been described as a postsynaptic proton receptor on hippocampal neurons influencing the intracellular Ca2+ concentration. In MS, ASIC1 seems to activate under acidic conditions predominating in the inflammatory CNS lesions leading to a Na+ and Ca2+ overload and consecutive damage and apoptosis of axons. Consecutively, in a MS mousemodel axonal damage was significantly less pronounced after administering amiloride, a clinically safe blocker of ASICs. So ASIC1 seems to play a major role in axonal degeneration in MS. To our knowledge no clinical studies have tested those promising in vitro results in humans so far.