Contribution of NTCP to Na+-dependent uptake of ligands by rat hepatocytes
| Compound | CLuptake(Hepatocyte) | Rhep | CLuptake(COS-7) | RCOS | Contribution of NTCP |
|---|---|---|---|---|---|
| μl/min/mg protein | μl/min/mg protein | % | |||
| Taurocholate | 60.8 | 1.00 | 80.9 | 1.00 | 100 |
| Glycocholate | 26.4 | 0.434 | 28.4 | 0.351 | 81 |
| Cholate | 18.0 | 0.296 | 9.30 | 0.115 | 39 |
| BSP-SG | 22.0 | 0.362 | ND | ND | ND |
| E3040 sulfate | 18.9 | 0.311 | ND | ND | ND |
| E3040 glucuronide | 3.79 | 0.0623 | ND | ND | ND |
| Ibuprofen | 14.3 | 0.235 | ND | ND | ND |
| Ouabain | 1.16 | 0.0191 | ND | ND | ND |
Data shown in figures 2 and 5 were used to determine the clearance for the Na+-dependent uptake by hepatocytes and that for NTCP-mediated uptake by transfected COS-7 cells. Based on these clearance values, Rhep and RCOSvalues were determined to calculate the contribution of NTCP.