PT  - JOURNAL ARTICLE
AU  - S R Dueker
AU  - M W Lamé
AU  - D Morin
AU  - D W Wilson
AU  - H J Segall
TI  - Guinea pig and rat hepatic microsomal metabolism of monocrotaline.
DP  - 1992 Mar 01
TA  - Drug Metabolism and Disposition
PG  - 275--280
VI  - 20
IP  - 2
4099  - http://dmd.aspetjournals.org/content/20/2/275.short
4100  - http://dmd.aspetjournals.org/content/20/2/275.full
SO  - Drug Metab Dispos1992 Mar 01; 20
AB  - The comparative metabolism of the pyrrolizidine alkaloid, [14C]monocrotaline, was studied using rat and guinea pig hepatic microsomes. Metabolites were quantified to the nanomole level using HPLC and radiometric detection. Triorthocresylphosphate and carbon monoxide were used to assess the involvement of carboxylesterases and cytochrome P-450 in the hepatic microsomal metabolism of monocrotaline, respectively. Esterase hydrolysis accounted for 92% of the metabolism in the guinea pig; the rat displayed no esterase activity. This result may explain the guinea pig's resistance to pyrrolizidine alkaloid toxicity. Dehydropyrrole was found to be the major pyrrolic metabolite in the guinea pig, although colorimetric analysis indicated multiple pyrrolic moieties in the rat microsomal incubations.