[Effect of aflatoxin B1 on monooxygenase activity in liver microsomes exposed to cytochrome P-450].

Effect of aflatoxin B1 (AFB1) on microsomal ethoxycumarindeethylase (ECDE) and amidopyrindemethylase (APDM) activities in liver of Wistar rats treated with inductors of different forms of cytochrome P-450 (P-450) 3-methylcholanthrene (3-MC) and phenobarbital (PB) were studied. AFB1 caused strong inhibition of ECDE activity, induced by 3-MC. 150 for AFB1 was equal 3.2 10-5. In the same time AFB1 did not effect on basal and PB induced ECDE and APDM activities. Participation of MC induced forms of cytochrome P-450 (P-448) in activation of AFB1 is supposed.