Comparison of the Induction Course, Biophysical Chemical Interactions and Photochemical Action Spectra of Phenobarbital and 3-Methylcholanthrene Induced Hepatic Microsomal P-450
That the P-450-dependent microsomal mixed function oxidase systems induced in rat livers by polycyclic hydrocarbons (3-methyl-cholanthrene (3-MC)) are different from those induced by phenobarbital (PB) was first reported by Sladek and Mannering (1966). More recently Fouts (1973) has observed that 3-MC is much less effective than phenobarbital in inducing the microsomal electron transport system necessary for reduction of P-450. It is likely, therefore, that during the course of induction of enzyme activity with polycyclic hydrocarbons and the decline of this activity to preinduc-tion levels there would be not only differences in the type of P-450 from that in PB-induced animals, but also changes in the reductive capacity of the microsomal electron transport system.
KeywordsSpectral Change Difference Spectrum Action Spectrum Polycyclic Hydrocarbon Demethylase Activity
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