title: In Vitro Drug Metabolism Using Liver Microsomes.
abstract: Knowledge of the metabolic stability of newly discovered drug candidates eliminated by metabolism is essential for predicting the pharmacokinetic (PK) parameters that underpin dosing and dosage frequency. Further, characterization of the enzyme(s) responsible for metabolism (reaction phenotyping) allows prediction, at least at the qualitative level, of factors (including metabolic drug-drug interactions) likely to alter the clearance of both new chemical entities (NCEs) and established drugs. Microsomes are typically used as the enzyme source for the measurement of metabolic stability and for reaction phenotyping because they express the major drug-metabolizing enzymes cytochrome P450 (CYP) and UDP-glucuronosyltransferase (UGT), along with others that contribute to drug metabolism. Described in this unit are methods for microsome isolation, as well as for the determination of metabolic stability and metabolite formation (including kinetics). © 2016 by John Wiley & Sons, Inc.
authors.affiliation: Department of Clinical Pharmacology, School of Medicine, Flinders University, Adelaide, South Australia, Australia.
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Knights
authors.affiliation: Corning Gentest Contract Research, Corning Incorporated Life Sciences, Woburn, Massachusetts.
authors.forename: David M
authors.initials: DM
authors.lastname: Stresser
authors.affiliation: Department of Clinical Pharmacology and Flinders Centre for Innovation in Cancer, School of Medicine, Flinders University, Adelaide, South Australia, Australia.
authors.forename: John O
authors.initials: JO
authors.lastname: Miners
authors.affiliation: Corning Incorporated, Tewksbury, Massachusetts.
authors.forename: Charles L
authors.initials: CL
authors.lastname: Crespi
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D055808:Drug Discovery; D014453:Glucuronosyltransferase / Q000378:metabolism; D057166:High-Throughput Screening Assays; D006801:Humans; D008862:Microsomes, Liver / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism*; D004364:Pharmaceutical Preparations / Q000378:metabolism*; D053719:Tandem Mass Spectrometry; D015215:Zidovudine / Q000378:metabolism*
chemical_list: D004364:Pharmaceutical Preparations; D015215:Zidovudine; D003577:Cytochrome P-450 Enzyme System; D014453:Glucuronosyltransferase
keywords: in vitro drug metabolism; liver microsomes; metabolic stability; microsome isolation