TABLE 6.

Subcellular localization of efflux Mdr transporters in various species

For each transporter, the apical or basolateral localization in a particular tissue and/or species is provided. Species included rat (R), mouse (M), human (H), and bovine (B). Detailed information regarding particular cellular populations or regions of the tissue are provided for some transporter isoforms.

Cellular Localization	Tissue	Species	Cell Types	References
Mdr1a/1b/MDR1
Apical	Liver	H, R	Hepatocytes, cholangiocytes	Gigliozzi et al., 2000; Scheffer et al., 2002c
Apical	Brain	M, R	Endothelial cells, choroid plexus	Schinkel et al., 1994; Rao et al., 1999; Miller et al., 2000
Apical	Placenta	M, H	Syncytiotrophoblasts	Lankas et al., 1998; St-Pierre et al., 2000
Apical	Fetal membranes	M	Visceral yolk sac	Lankas et al., 1998
Apical	Colon	M	Epithelial cells	Panwala et al., 1998
Apical	Pancreas	H	Small epithelial ducts	Scheffer et al., 2002b
Apical	Small intestine	R	Enterocytes (jejunum/ileum)	Ujhazy et al., 2001; Rost et al., 2002
Apical	Lung	H	Bronchial and bronchiolar epithelium	Scheffer et al., 2002c
Apical	Kidney	R, H	Proximal tubule cells	Jette et al., 1996; Ernest et al., 1997
N.D.	Testes	H	Myoid, Leydig, capillary endothelial cells	Bart et al., 2004
N.D.	Inner ear	M	Capillary endothelial cells	Zhang et al., 2000
N.D.	Adrenal gland	H	Cortex	Scheffer et al., 2002b
Mdr2/MDR3
Apical	Liver	M, H	Hepatocytes	Buschman et al., 1992; de Vree et al., 1998

N.D., not determined.