RT Journal Article SR Electronic T1 Characterization of mixed-function oxidases and purified cytochrome P-450 of livers of house musk shrew, Suncus murinus. JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 151 OP 155 VO 16 IS 1 A1 K Mizokami A1 M Fukuhara A1 T Nohmi A1 M Sunouchi A1 K Fujimori A1 A Takanaka A1 Y Omori YR 1988 UL http://dmd.aspetjournals.org/content/16/1/151.abstract AB Characteristics of mixed-function oxidases in the liver of house musk shrew, Suncus murinus, were studied. The basal level of cytochrome P-450 and the activity of drug-metabolizing enzyme in hepatic microsomes of Suncus murinus is relatively lower than that of rats, while the level of cytochrome b5 and NADPH-cytochrome c reductase is approximately the same as that of rats. The treatment of Suncus murinus with phenobarbital and 3-methylcholanthrene elevated the level of cytochrome P-450 and the activity of drug-metabolizing enzymes, but not the level of cytochrome b5. Two distinct forms of cytochrome P-450 have been purified from hepatic microsomes of 3-methylcholanthrene-treated Suncus murinus. These forms have their absorption maximum at 448.0 nm and 448.5 nm in CO-bound reduced form, and one is in the high-spin state and the other is in the low-spin state. They are different in their molecular weights (53,500 and 55,000) and in their spectral and catalytic properties. Characteristics of these forms were compared with those of the major forms of cytochrome P-450 purified from livers of rats treated with 3-methylcholanthrene.