PT  - JOURNAL ARTICLE
AU  - C Lindberg
AU  - C Roos
AU  - A Tunek
AU  - L A Svensson
TI  - Metabolism of bambuterol in rat liver microsomes: identification of hydroxylated and demethylated products by liquid chromatography mass spectrometry.
DP  - 1989 May 01
TA  - Drug Metabolism and Disposition
PG  - 311--322
VI  - 17
IP  - 3
4099  - http://dmd.aspetjournals.org/content/17/3/311.short
4100  - http://dmd.aspetjournals.org/content/17/3/311.full
SO  - Drug Metab Dispos1989 May 01; 17
AB  - The oxidative metabolism of (R,S)-bambuterol in rat liver microsomes was studied. Metabolite fractions were analyzed by thermospray LC-MS. The use of an equimolar mixture of deuterium-labeled and unlabeled bambuterol facilitated the mass spectrometric identification of the metabolites. Six metabolites, formed via hydroxylation, demethylation, and hydrolytic reactions, were identified. The demethylated metabolites were found to be chemically unstable under physiological conditions. It is likely that the complex biotransformation of bambuterol into terbutaline is one factor contributing to the long duration of action of bambuterol.