TABLE 2

In vitro P-gp transport activities and reconstruction of K_{p brain} ratios from in vitro data for 11 P-gp substrates

Based on the results shown in Fig. 1, the P_app, flux ratio, and in vitro P-gp efflux ratio across LLC-PK1/L-mdr1a cell monolayers were calculated as described under Materials and Methods. Reconstructed K_{p brain} ratios were calculated from the in vitro P-gp efflux ratio and the mdr1a protein expression amounts according to equation 7. Each value represents the mean ± S.E.M. The S.E.M. was calculated according to the law of propagation of error.

Substrate	LLC-PK1			l-mdr1a			In Vitro P-gp Efflux Ratio	Reconstructed K_{p brain} Ratio
	P_app (×10^{− 6} cm/s)		Flux Ratio	P_app (×10^{− 6} cm/s)		Flux Ratio
	A to B	B to A	Flux Ratio	A to B	B to A	Flux Ratio
Quinidine	57.2 ± 7.6	80.5 ± 3.1	1.41 ± 0.14	3.16 ± 0.10	146 ± 10	46.4 ± 2.4	33.0 ± 2.6	30.7 ± 3.0
Loperamide	49.7 ± 1.9	98.0 ± 4.0	1.97 ± 0.08	5.49 ± 0.51	271 ± 19	49.3 ± 4.1	25.0 ± 1.6	23.3 ± 2.1
Digoxin	11.8 ± 2.3	18.8 ± 0.9	1.60 ± 0.23	1.13 ± 0.11	31.9 ± 1.9	28.4 ± 2.2	17.8 ± 2.1	16.6 ± 1.9
Risperidone	96.3 ± 2.3	58.7 ± 4.9	0.610 ± 0.037	23.3 ± 0.9	150 ± 5	6.45 ± 0.24	10.6 ± 0.5	9.89 ± 0.82
Indinavir	14.4 ± 2.7	20.5 ± 1.7	1.42 ± 0.21	3.33 ± 0.23	45.3 ± 1.7	13.6 ± 0.8	9.55 ± 1.04	8.94 ± 0.97
Dexamethasone	29.5 ± 0.2	36.5 ± 0.6	1.24 ± 0.02	6.91 ± 0.22	102 ± 2	14.7 ± 0.4	11.9 ± 0.2	11.1 ± 0.9
Vinblastine	24.2 ± 7.7	38.7 ± 5.7	1.60 ± 0.39	2.83 ± 0.56	56.1 ± 7.1	19.8 ± 3.3	12.4 ± 2.6	11.6 ± 2.0
Paclitaxel	20.5 ± 2.9	33.2 ± 4.2	1.62 ± 0.22	2.70 ± 0.25	53.8 ± 1.8	19.9 ± 1.4	12.3 ± 1.3	11.5 ± 1.3
Verapamil	73.5 ± 6.6	39.0 ± 1.0	0.530 ± 0.035	11.9 ± 0.1	84.0 ± 4.9	7.05 ± 0.30	13.3 ± 0.7	12.4 ± 1.1
Loratadine	23.1 ± 4.1	33.1 ± 3.1	1.43 ± 0.21	32.0 ± 1.7	80.2 ± 4.6	2.51 ± 0.14	1.75 ± 0.19	1.70 ± 0.14
Diazepam	31.8 ± 2.1	43.5 ± 1.9	1.37 ± 0.08	57.3 ± 4.5	67.4 ± 2.5	1.18 ± 0.07	0.859 ± 0.050	0.869 ± 0.036