Table 1

Induction of glucuronidation in rat liver microsomes

Rat speciesInducerRate of NNAL-Gluc FormationRatio of NNAL-Gluc I: NNAL-Gluc IIRate of Aglycone-gluc Formation
pmol/mg/min1-a-fold induction1-baglyconenmol/mg/min-fold induction1-b
SDCorn oil (n= 3)1-c 1-d 0.94  ± 0.324.65  ± 0.484-NP53  ± 42
3-MC (n = 5)1.10  ± 0.211.2 4.58  ± 0.414-NP145  ± 472.71-e
H2O (n = 3)1-c 1.01  ± 0.284.25  ± 0.704-NP45  ± 13
bilirubin1-f 1.00  ± 0.11
PB (n = 4)1.74  ± 0.391.71-e 4.80  ± 0.494-NP92  ± 242.11-e
Clofibric acid (n = 5)1.41  ± 0.301.4 4.37  ± 0.604-NP46  ± 281.0
bilirubin1-f 1.86  ± 0.421.91-e
WistarNone (n = 5)0.46  ± 0.083.46  ± 1.104-NP32  ± 17
BHA (n = 5)0.78  ± 0.301.71-e 4.03  ± 0.594-NP122  ± 473.81-g
BHT (n = 5)1.24  ± 0.492.61-h 5.35  ± 1.101-i 4-NP125  ± 293.91-j
  • 1-a Data are expressed as mean ± S.D. for triplicate assays, performed at 37°C for 40 min using 2 mM [14C]UDPGA (0.5 μCi/reaction) as described in Materials and Methods.

  • 1-b Fold-induction data were determined by comparing rates of formation of glucuronidated metabolites in rat liver microsomes from induced rats with the corresponding values in rat liver microsomes from control rats.

  • 1-c Corn oil: control SD rats for 3-MC treatment; H2O: control SD rats for PB and clofibric acid treatment.

  • 1-d Numbers in parenthesis indicate the number of rats per group.

  • 1-e p < .05, Student’s t test.

  • 1-f Glucuronidation assays were performed using 50 μM bilirubin.

  • 1-g p < .005, Student’s t test.

  • 1-h p < .01, Student’s t test.

  • 1-i p < .05, Student’s t test, as compared to untreated Wistar control group.

  • 1-j p < .001, Student’s t test.