Under anaerobic reducing conditions various polyhalogenated methanes (CBr 4, CCl 4, CCl 3F, CCl 3Br, CCl 3CN, CHI 3, CHBr 3, and CHCl 3) form complexes with ferrous cytochrome P450 with absorption peaks in the difference spectra ranging between 450 and 470 nm. Carbon monoxide was detected as a metabolic product of the interaction. Inhibition experiments indicated the involvement of cytochrome P450 in the reduction process, and a reaction sequence is proposed to account for these findings. Comparison of cytochrome P450 complex formation using liver microsomal preparations from phenobarbital- and 3,4 benzpyrene-treated rats showed differences which could be accounted for by decreased stability of the halogenomethane complex with the 3,4 benzpyrene-induced form of cytochrome P450.
|Number of pages||8|
|Publication status||Published - 1 Dec 1977|