TABLE 1

Steady-state hepatic unbound concentrations and excretory unbound intrinsic clearances (mean ± S.D., n = 3-4/group) of sulfate and glucuronide conjugates formed in the liver from the respective parent compounds

	C57BL/6	Abcc2(−/−)	Abcg2(−/−)
Liver mass (g)	1.18±0.02	1.4±0.2	1.2±0.2
Bile flow (μl/min/g liver)	1.0±0.3	0.7±0.1	0.9±0.2
Acetaminophen sulfate
C_{liver unbound, ss} (nM)	171±32	140±64	222±49
Cl_{bile, ss} (μl/min/g liver)	18±5	26±6	2.3±0.2^*
Cl_{basolateral, ss} (μl/min/g liver)	289±23	272±63	189±42
Acetaminophen glucuronide
C_{liver unbound, ss} (nM)	2917±1257	972±548	3628±530
Cl_{bile, ss} (μl/min/g liver)	2±1	1.8±0.6	0.29±0.09
Cl_{basolateral, ss} (μl/min/g liver)	175±97	554±313	99±18
4-Methylumbelliferyl sulfate
C_{liver unbound, ss} (nM)	104±22	55±18^*	162±22^*
Cl_{bile, ss} (μl/min/g liver)	2199±495	4096±254^*	2±1^*
Cl_{basolateral, ss} (μl/min/g liver)	3669±1888	6272±1964	3296±773
4-Methylumbelliferyl glucuronide
C_{liver unbound, ss} (nM)	1717±402	1210±547	2824±552^*
Cl_{bile, ss} (μl/min/g liver)	88±43	59±28	24±1
Cl_{basolateral, ss} (μl/min/g liver)	703±387	1152±892	398±45
Harmol sulfate
C_{liver unbound, ss} (nM)	399±103	342±79	511±100
Cl_{bile, ss} (μl/min/g liver)	1081±417	1211±246	12±1^*
Cl_{basolateral, ss} (μl/min/g liver)	562±257	497±152	1254±149^*
Harmol glucuronide
Cl_{bile, ss} (μl/min/g liver)	315±205	248±157	14±2
Cl_{basolateral, ss} (μl/min/g liver)	219±80	204±95	396±51^*

↵* p < 0.05, knockout vs. wild type.