Table 4.

Maternal brain 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). 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
Brain AUC0-480min of NBUP (μg×min×g1)	0.8 [0.7, 0.9]	47.3 [39.9 52.4]	< 0.0001	42.8 [37.0, 47.9]	< 0.0001
Fold-change	1.0	60.1		54.4
Brain/Maternal plasma AUC ratio of NBUP	0.2 [0.1, 0.3]	6.7 [4.7, 8.1]	< 0.01	4.9 [3.2, 6.5]	< 0.01
Fold-change	1.0	34.1		24.5
Brain AUC0-480min of NBUP-G (μg×min×g-1)	10.7 [8.4, 13.1]	23.6 [20.6, 27.4]	0.8	56.1 [48.1, 66.3]	<0.005
Fold-change	1.0	2.2		5.2
Brain/Maternal plasma AUC ratio of NBUP-G	0.4 [0.3, 0.5]	0.25 [0.18, 0.37]	0.26	0.48 [0.36, 0.65]	0.9
Fold-change	1.0	0.6		1.2