title: 5-Methoxypsoralen inhibits 6-hydroxylation of melatonin in the rat.
abstract: Pharmacokinetic studies of exogenous melatonin (100 or 1 micrograms) administered to 5-methoxypsoralen (MOP)-treated rats, showed that MOP administration induced an increase in the half-life of melatonin from 22 to 67 min. This delayed degradation of melatonin was the consequence of 5-MOP-induced inhibition of the 6-hydroxylation of melatonin. Under in vitro experimental conditions, 5-MOP did not affect melatonin synthesis and release. These results demonstrate that the elevated plasma melatonin concentrations observed in vivo following 5-MOP administration is due to inhibition of the hydroxylation of endogenous melatonin.
authors.affiliation: URA-CNRS 1332, Université Louis-Pasteur, Strasbourg, France.
authors.forename: F
authors.initials: F
authors.lastname: Mauviard
authors.forename: F
authors.initials: F
authors.lastname: Raynaud
authors.forename: M
authors.initials: M
authors.lastname: Geoffriau
authors.forename: B
authors.initials: B
authors.lastname: Claustrat
authors.forename: P
authors.initials: P
authors.lastname: Pévet
mesh_terms: D000078223:5-Methoxypsoralen; D000818:Animals; D006900:Hydroxylation / Q000187:drug effects; D008297:Male; D008550:Melatonin / Q000031:analogs & derivatives / Q000097:blood / Q000378:metabolism* / Q000493:pharmacokinetics; D008730:Methoxsalen / Q000031:analogs & derivatives* / Q000494:pharmacology; D009924:Organ Culture Techniques; D010870:Pineal Gland / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: C054513:6-sulfatoxymelatonin; D000078223:5-Methoxypsoralen; D008550:Melatonin; C012365:6-hydroxymelatonin; D008730:Methoxsalen