Stereoselective metabolism of benzo[c]phenanthrene to the procarcinogenic tras-3,4-dihydrodiol.

The enantiomeric compositions of benzo[c]phenanthrene -3,4-dihydrodiol, a metabolic precursor of the ultimate carcinogenic bay-region 3,4-dihydrodiol-1,2-epoxides, formed in the metabolism of BcPh by liver microsomes from untreated, phenobarbital (PB)-treated, 3-methylcholanthrene (MC)-treated and polychlorinated biphenyls (PCB; Aroclor 1254)-treated rats of the Sprague-Dawley and Long-Evans strain were each determined by chiral stationary-phase h.p.l.c. and circular dichroism spectral analyses. The percentage of 3R,4R enantiomer in the -3,4-dihydrodiol metabolite of BcPh varies, depending on the concentration of liver microsomal enzymes used and the time of incubation: 29–30% (control), 46–54% (PB), 94–100% (MC) and 90–99% (PCB). [ABSTRACT FROM PUBLISHER]