Influence of rifampicin on the pharmacokinetics of salvianolic acid B may involve inhibition of organic anion transporting polypeptide (Oatp) mediated influx.

This article studied the possible effect of rifampicin (RIF), an inhibitor of organic anion transporting polypeptide (Oatp), on the pharmacokinetics of salvianolic acid B (SAB) in rats. Rifampicin was administered intravenously 15 min prior to SAB (5 mg/kg) in rats at doses of 0, 5.0, 10.0 and 20.0 mg/kg, respectively. The concentrations of SAB in plasma and bile were determined using a Shimadzu HPLC system coupled to a LC-MS-2010EV mass spectrometer. Compared with the control group, the AUC(0-t) and C(max) values of SAB were increased significantly, while the CL(total) and CL(bile) were decreased significantly. These results suggested that pretreatment with rifampicin prior to SAB administration could decrease significantly the total and bile elimination of SAB and alter its pharmacokinetic profiles. The influence of rifampicin on the pharmacokinetics of SAB may be attributed to the inhibition of Oatp-mediated influx.