title: Spectroscopic quantitation of cytochrome P-450 in human lung microsomes.
abstract: The cytochrome P-450 content of human lung microsomes was measured by difference spectroscopy of the carbon monoxide-complexed hemoprotein. These measurements were only possible after the microsome preparation had been subjected to centrifugation over a discontinuous sucrose gradient, to remove an opaque black contaminant. The specific concentration of total cytochrome P-450 in human lung microsomes is essentially identical to that of microsomes prepared under identical conditions from untreated baboon lungs, but is only 0.7% of the specific content found in lung microsomes from untreated rabbits. These measurements correspond well to the observed metabolic capacities of the various microsome samples.
authors.affiliation: Department of Pharmacology, University of Illinois College of Medicine, Chicago 60612.
authors.forename: C W
authors.initials: CW
authors.lastname: Wheeler
authors.forename: T M
authors.initials: TM
authors.lastname: Guenthner
mesh_terms: D015660:7-Alkoxycoumarin O-Dealkylase / Q000378:metabolism; D000818:Animals; D001189:Aryl Hydrocarbon Hydroxylases / Q000378:metabolism; D002248:Carbon Monoxide / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis*; D006801:Humans; D008168:Lung / Q000201:enzymology*; D008861:Microsomes / Q000201:enzymology*; D010215:Papio; D011817:Rabbits; D013045:Species Specificity; D013053:Spectrophotometry
chemical_list: D002248:Carbon Monoxide; D003577:Cytochrome P-450 Enzyme System; D015660:7-Alkoxycoumarin O-Dealkylase; D001189:Aryl Hydrocarbon Hydroxylases