TABLE 1

Contribution of OATP1B1, OATP1B3, and OATP2B1 to the hepatic uptake of pitavastatin determined by the relative expression level

Hepatocyte Lot	Ratio of Expression Level^a (Hepatocyte/Expression System)					Estimated Clearance^b
Hepatocyte Lot		R_exp,OATP1B1	R_exp,OATP1B3	R_exp,OATP2B1	OATP1B1	OATP1B3	OATP2B1
					μl/min/10⁶ cells
OCF	2.90^c	1.21^c	0.200	222	37.0	0.658
				85.5%	14.3%	0.253%
094	1.58^c	0.930^c	0.152	121	28.5	0.500
				80.7%	19.0%	0.333%
ETR	0.890^c	0.737^c	0.112	68.2	22.6	0.368
				74.8%	24.8%	0.405%

↵ a Ratio of the expression level was determined by the intensity of the specific band in the crude membrane prepared from human hepatocytes (per 10⁶ cells) divided by that in the crude membrane from transporter-expressing cells (per milligram) in Western blot analysis.
↵ b In the `Estimated Clearance' column, each percentage value indicates the percentage of the OATP1B1-, OATP1B3-, or OATP2B1-mediated uptake clearance relative to the sum of the estimated clearance mediated by OATP1B1, OATP1B3, and OATP2B1. The details of this estimation are described under Materials and Methods.
↵ c Values from Hirano et al. (2004).