@article {Legrum790, author = {W Legrum and J Frahseck}, title = {Acceleration of 7-[methoxy-14C]coumarin-derived carbon dioxide exhalation by cobalt pretreatment in mice.}, volume = {221}, number = {3}, pages = {790--794}, year = {1982}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {Pretreatment of rats with cobaltous chloride has been shown previously to reduce the content of cytochrome P-450 in the hepatic microsomal protein. This is accompanied by a corresponding decrease in substrate oxidation, e.g. ethyl morphine demethylation, in vitro. The present paper shows that pretreatment of C57BL/6J Han mice with 40 mg of CoCl2/kg/day for 2 days results in a decrease of cytochrome P-450 to 60\% of its original value. This is accompanied by a corresponding decrease in overall rate of [14C]methacetin demethylation as measured by 14CO2 exhalation. However, when 7-[methoxy-14C]coumarin is the substrate, cobalt-pretreated animals exhale twice as much 14CO2 than normal animals. Considering the decrease in cytochrome P-450 (and assuming linear relationship between metabolic activity and cytochrome P-450 content), this observation suggested a 2.5-fold increase in the specific activity of the remaining cytochrome P-450. This was found to be true in vitro. It is concluded that cobalt pretreatment of mice leads to an enhanced in vivo demethylation rate of 7-[methoxy-14C]coumarin which is explained by a considerably higher molecular monooxygenase activity toward this substrate that is found in vitro.}, issn = {0022-3565}, URL = {https://jpet.aspetjournals.org/content/221/3/790}, eprint = {https://jpet.aspetjournals.org/content/221/3/790.full.pdf}, journal = {Journal of Pharmacology and Experimental Therapeutics} }