Abstract
1. O-Demethylation of 1-methoxyindole-3-carboxylk acid, in vitro, by determination of liberated formaldehyde, has been demonstrated using fortified 15000 g rat liver supernatant fraction.
2. Results have been compared to those similarly obtained with a standard O-demethylation substrate, 4-nitroanisole, to substantiate and quantify the extent of the reaction.
3. Km values for 4-nitranisole and methoxyindole-3-carboxylic acid were 8.9 and 6.5 mm, while Vmax values were 4.9, and 5.2 nmol HCHO produced/mg protein per min.
4. The significance of the metabolic O-demethylation reaction for N-methoxyindoles as a novel metabolic pathway is discussed in terms of pharmacological activity and biological reactivity.