title: Phospholipid requirement for 2-acetamidofluorene N-and ring-hydroxylation by hamster liver microsomal cytochrome P-450 enzyme system.
abstract: A phospholipid requirement of 2-acetamidofluorene N- and ring-hydroxylation was investigated with partially delipidated microsomal fraction from livers of 3-methylcholanthrene-pretreated hamsters. Butan-1-ol extraction of microsomal fraction removed 90% of the total lipid content without any appreciable effect on microsomal proteins. Such extracted microsomal fractions had much lower capacity to N- and ring-hydroxylate 2-acetamidofluorene: 25 and 44% of control respectively. Addition of butan-1-ol-extracted total lipid restored both oxidations to some extent, whereas addition of phosphatidylcholine fraction restored both oxidations almost completely. Addition of synthetic phospholipid, dilauroyl phosphatidylcholine, restored both oxidations to a large extent, whereas synthetic dipalmitoyl or distearoyl phosphatidylcholine was ineffective in restoring these oxidations.
mesh_terms: D015073:2-Acetylaminofluorene / Q000378:metabolism*; D000818:Animals; D006224:Cricetinae; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D005449:Fluorenes / Q000378:metabolism*; D006900:Hydroxylation; D066298:In Vitro Techniques; D008748:Methylcholanthrene / Q000494:pharmacology; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism*
chemical_list: D005449:Fluorenes; D010743:Phospholipids; D008748:Methylcholanthrene; D003577:Cytochrome P-450 Enzyme System; D015073:2-Acetylaminofluorene