Animal drug-metabolizing enzyme activities

Table I. Drug-metabolizing enzyme activities in liver of animals.

Unlike renal function, hepatic maturation is generally believed to be a two-stage process with the major development completed at 4 weeks postpartum and tlie second stage completed by about 10 weeks of age. In sheep, for example, tlie activity of a number of hepatic drug-metabolizing enzymes was found to be relatively low in animals aged up to 6 months compared with adult individuals... 

In animals, oral exposure to carbon disulfide does not appear to cause significant liver toxicity, although the data are limited. Male mice orally exposed to 3-300 mg/kg/day (1-14 days) have shown rapid, reversible, dose-related suppression of hepatic microsomal enzymes (Masuda and Yasoshima 1988 Masuda et al. 1986). An acute-duration MRL of 0.01 mg/kg/day was derived based on dose-dependent decreases in the activities of liver microsomal drug-metabolizing enzymes in mice (Masuda et al. 1986). The LOAEL for this effect was 3 mg/kg/day. The following enzyme activities were decreased ... 

These are potent herbicides54,55. Among about 180 prepared analogs (R = 4-Me, R = H), the compound has been found to be very active and was introduced commercially under the names of Destun or Perfluidone. This compound stimulates to some extent some hepatic drug metabolizing enzymes. The above effect varies with different animal species56,57. Related compounds (15, R = 3-PhCO-, R = -COOEt) possess antipyretic and antiinflammatory activity58. 

---