Effects of streptolysin O, picibanil (OK 432) and interferon α2A on cytochrome P-450-dependent monooxygenases and arylamine N-acetyltransferase in rat liver

AbstractStreptolysin O, a thiol-activated exotoxin from group A β-haemolytic streptococci, caused a dose-dependent depression of aniline hydroxylase, aminopyrine N-demethylase and ethylmorphine N-demethylase activities when added into the hepatic microsomal mixtures from male rats at concentrations 0.02 -0.4 HU/mL in vitro. the activities of 7-ethoxycoumarin O-deethylase, 7-ethylresorufin O-deethylase and 7-pentylresorufin O-depentylase were not altered with the used concentrations of the toxin. Specific antibody against haemolytic action of streptolysin O added to incubation mixtures in vitro was not able to protect streptolysin-sensitive monooxygenases from the inhibition. the addition of streptolysin 0 (0.01 -0.8 HU/mL) into the cytosol-containing medium did not significantly influence the activity of procainamide N-acetyltransferase. Immunomodulators picibanil (OK 432) and human recombinant interferon α2A which are known to suppress oxidative metabolism in vivo in humans and animals, were without effe...