Table 2.

Maternal plasma AUCs of norbuprenorphine (NBUP) and norbuprenorphine-3-β-D-glucuronide (NBUP-G) after retro-orbital injection (1 mg/kg) to pregnant mice on gd 15 over 480 min. Data are reported as mean (95% confidence interval). The NBUP-G/NBUP AUC ratios were calculated based on molar concentrations of NBUP and NBUP-G in maternal plasma. Differences between the analyte AUCs or the AUC ratios of wild-type and Abcb1a^-/-/1b^-/-or Abcb1a^-/-/1b^-/-/Abcg2^-/- mice were calculated using bootstrapping as described in the Materials and methods section. The p values were corrected for multiple testing using the Bonferroni method.

Parameter	Genotype
	Wild-type	Abcb1a-/-/1b-/-	p	Abcb1a-/-/1b-/-/Abcg2-/-	p
AUC0-480min of NBUP (μg×min×mL-1)	4.1 [3.6, 5.8]	7.1 [6.2, 9.4]	< 0.005	8.7 [7.1, 11.3]	< 0.005
Fold-change	1.0	1.8		2.2
AUC0-480min of NBUP-G (μg×min×mL-1)	26.8 [21.8, 34.2]	95.0 [75.5,120.8]	<0.0001	116.7 [84.4, 154.1]	< 0.0001
Fold-change	1.0	3.6		4.4
NBUP-G/NBUP maternal plasma AUC ratio	4.6 [3.7, 5.8]	9.4 [7.1, 11.3]	0.09	9.4 [6.1, 13.5]	0.3
Fold-change	1.0	2.0		2.0