Table 1

Comparison of epoxide formation from VCH in microsomes from female B6C3F1 mice1-a or Fischer-344 rats treated with either 7.5 mmol/kg VCH i.p. for 10 days, or 80 mg/kg i.p. PB for 5 days

MetaboliteTreatment GroupMouseRat
nmol/mg microsomal protein/60 min
VCH-1,2-epoxidecontrol54.0  ± 8.01-b 28.3  ± 2.8
phenobarbital318.6  ± 8.7 (5.9)1-c 79.3  ± 7.1 (2.8)
VCH205.2  ± 36.5 (3.8)56.1  ± 5.3 (2.0)
VCH-7,8-epoxidecontrol36.6  ± 5.222.0  ± 5.3
phenobarbital75.7  ± 1.3 (2.1)35.0  ± 3.3 (1.6)
VCH75.0  ± 5.0 (2.0)39.6  ± 5.3 (1.8)
VCDcontrolN.D.N.D.
phenobarbital7.6  ± 0.9N.D.
VCH6.3  ± 0.9N.D.
  • N.D., not-detectable.

  • 1-a  n = 4 groups of microsomes were pooled from mice (4 mice/group, 16 mice total/treatment). Microsomes were prepared from individual rats (four rats per treatment).

  • 1-b  Values represent mean (±S.D.) nanomoles of epoxide formed per milligrams of protein after 60 min.

  • 1-c  Values in parenthesis represent significant (p < 0.05) fold-increase in epoxide metabolite formation over control microsomal incubations.