Polymorphic sparteine metabolism and amyotrophic lateral sclerosis.

The activity of detoxication with the cytochrome P450 family of enzymes was studied in patients with amyotrophic lateral sclerosis (ALS). The metabolic ratio (MR) of sparteine sulphate was measured, and the population of phenotypes for sparteine nitro (N)-oxidation was determined in 30 patients with ALS and 41 controls for the assay of the sparteine N-oxidation by the cytochrome P450 enzymes. A lower MR and higher frequency of efficient metabolizers were observed in the ALS group, suggesting that there is efficient sparteine N-oxidation by cytochrome P450 pathways in ALS. This tendency was more marked in 15 patients with ALS aged under 60 years.