Effect of Mycobacterium butyricum on the hepatic cytochrome P-450 system of the mouse: influence of anti-inflammatory drug.

1. M. butyricum administration to rats induces arthritis and impairment in hepatic cytochrome P-450 activity. 2. This work was performed to verify if M. butyricum administrated to mice produces similar effects on cytochrome P-450 hepatic without involvement of articular lesions. 3. We also studied the role of arachidonate metabolites in the genesis and perpetuation of hepatic injury. 4. Intraperitoneal M. butyricum administration to mice increased sleeping time induced by pentobarbital and decreased both aminopyrine N-demethylase (AND) and aniline p-hydroxylase (APH) activities without producing articular inflammation. 5. Only preventative oral administration of indomethacin or dexamethasone during the week before M. butyricum injection avoided drug-metabolizing system alterations. 6. Our results suggest a possible link between arachidonate metabolites inhibited by indomethacin or dexamethasone and the genesis of cytochrome P-450 disfunction.