PortaCellTec biosciences GmbH


Molecular structure and tissue distribution
OATP1B1 (previously known as OATP-C) is highly expressed in liver where it is localized to the basolateral membrane of the hepatocytes. The gene for OATP1B1 is located on chromosome 12p12. The two hepatocyte-specific OATPs OATP1B1 and OATP1B3 seem to have no orthologous proteins in mouse or rat. Therefore, the transferability of animal data to humans is difficult with regard to OATPs.

Interaction of OATP1B1 with endogenous compounds and drugs

OATP1B1 mediates the uptake of many different drugs from blood into hepatocytes. Endogenous compounds that are transported by OATP1B1 are bile salts like taurocholate but also estrone sulfate and sulfobromophthalein (BSP) which are used as model substrates.
Drug substrates of OATP1B1 are e.g. statins (pravastatin, rosuvastatin), antibiotics (rifampicin, benzylpenicillin) and cytostatics (methotrexate). For some drugs it seems that a genetic variation (521T>C; V174A) is associated with an altered pharmacokinetic.

Figure 1 Time dependency experiments with estrone-3-sulfate Figure 2 Inhibition of OATP substrates by rifampicin.




New validated products:

  • mNtcp
  • mOct1


3rd German Pharm-Tox Summit
Göttingen, Germany
26 February - 1 March 2018

Saarbrücken, Germany
8 March 2018


AAPS Workshop
Virginia, USA
16 - 18 April 2018


20th Barrier- and

Bad Herrenalb, Germany
7 - 9 May 2018

Greifswalder Transporttage 2018
Greifswald, Germany
7 - 9 September 2018


Guidance for Industry (FDA and EMA)