Amyotrophic lateral sclerosis

Several aspects of amyotrophic lateral sclerosis are reviewed, with special emphasis on arguments based on etiological and pathogenic theories currently in vogue: free radicals, glutamate-induced toxic excitation, trophic factors, autoimmunity and axon transport. Each of these theories has inspired therapeutic trials, some of which are already completed and others are still in progress. More than one neurodegenerative mechanism may be involved in amyotrophic lateral sclerosis, meaning that it might be necessary to combine several drugs in future trials.