title: [Biotransformation processes in fertile hen's eggs. 1. Metabolic transformation of 7-ethoxycoumarin].
abstract: An alternative method for the investigation of biotransformations employing fertile chicken eggs has been developed. In these studies, solutions of 7-ethoxycoumarin were injected into the white of eggs from a standardized breed after brooding time of at least 8 days. After further incubation, the allantois was analyzed for metabolites of 7-ethoxycoumarin. The dealkylated metabolite of 7-ethoxycoumarin, namely 7-hydroxycoumarin, could be assayed in the allantois liquid by means of a new HPLC method. Furthermore, conjugates of 7-hydroxycoumarin, namely the glucuronid and the sulfate, can be detected indirectly in the allantois after conjugate cleavage. The inducability of the cytochrome P-450-dependent O-dealkylation has been studied with phenobarbital and 3-methylcholanthrene. An increase in the conversion of 7-ethoxycoumarin to 7-hydroxycoumarin was observed after addition of 3-methylcholanthrene. The detected metabolites demonstrate the usefulness of the developed model for studying biotransformation processes.
authors.affiliation: Pharmazeutisches Institut, Christian-Albrechts-Universität, Kiel.
authors.forename: B
authors.initials: B
authors.lastname: Clement
authors.forename: C
authors.initials: C
authors.lastname: Mladek
mesh_terms: D000818:Animals; D001711:Biotransformation; D002642:Chick Embryo; D002851:Chromatography, High Pressure Liquid; D003374:Coumarins / Q000493:pharmacokinetics*; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis / Q000378:metabolism; D004790:Enzyme Induction / Q000187:drug effects; D005965:Glucuronates / Q000378:metabolism; D008748:Methylcholanthrene / Q000494:pharmacology; D010047:Ovalbumin / Q000378:metabolism; D010634:Phenobarbital / Q000494:pharmacology; D013431:Sulfates / Q000378:metabolism
chemical_list: D003374:Coumarins; D005965:Glucuronates; D013431:Sulfates; C017299:7-ethoxycoumarin; D008748:Methylcholanthrene; D010047:Ovalbumin; D003577:Cytochrome P-450 Enzyme System; D010634:Phenobarbital
vernacular_title: Biotransformationsuntersuchungen im Hühnerei. Teil 1: Metabolische Umwandlung von 7-Ethoxycumarin.