The human multidrug resistance protein family
| Isoform | Other Names | Year Cloned | Primary Site of Expression | Expression in Brain |
|---|---|---|---|---|
| MRP1 | ABCC1 | 1992 | Ubiquitous | BBB, CP, AST, WB, MG |
| MRP2 | ABCC2; cMOAT | 1994 | Liver/kidney/gut | No |
| MRP3 | ABCC3; MOAT-D | 1996 | Liver/kidney/adrenals | BBB5-a |
| MRP4 | ABCC4; MOATB | 1996 | Prostate/lung/testis | BBB |
| MRP5 | ABCC5; MOAT-C | 1996 | Ubiquitous | BBB |
| MRP6 | ABCC6; MOAT-E | 1998 | Liver/kidney | BBB |
| MRP7 | ABCC10 | 2001 | Skin/stomach | WB |
MOAT, multispecific organic anion transporter; WB, whole brain homogenate; AST, astrocytes; MG, microglia.
↵5-a Expression in blood brain barrier is controversial. Generally the substrate specificity of MRP includes glucuronide, sulfate, and glutathione-conjugated compounds, large hydrophobic anions, and various cationic and neutral compounds in the presence of physiological concentrations of glutathione (Borst et al., 1999, 2000).