TABLE 1

Steady-state plasma and brain concentrations of erlotinib in wild-type, Mdr1a/b^−/−_, Bcrp1^−/−, and Mdr1a/b^−/−Bcrp1^−/− mice after a constant intraperitoneal infusion at a rate of 0.6 mg/h/kg

Data are presented as the mean ± S.D.

Genotype	n	Plasma Concentration	Brain Concentration	Brain-to-Plasma Ratio
		ng/ml	ng/g
FVB (wild-type)	4	72 ± 41	4.3 ± 5.5^a	0.02 ± 0.02
Bcrp1^−/−	4	71 ± 3	4.9 ± 2.9^a	0.07 ± 0.02
Mdr1a/b^−/−	4	81 ± 44	12 ± 2.8^a^,^b	0.09 ± 0.06^b
Mdr1a/b^−/−Bcrp1^−/−	4	99 ± 21	34 ± 17^b	0.62 ± 0.27^b

↵a P < 0.05 compared with corresponding plasma concentration.
↵b P < 0.05 compared with wild-type group.