Effect of omeprazole on pharmacokinetic parameters of imatinib in rats / 中国药房

ABSTRACT

OBJECTIVE To investigate the effects of omeprazole on pharmacokinetic parameters of imatinib in rats. METHODS According to body weight， the rats were divided into imatinib+low-dose， medium-dose， and high-dose omeprazole groups， imatinib group， with 6 rats in each group. They were given omeprazole suspension at the doses of 1.8， 3.6 and 7.2 g/kg， or 0.5% sodium carboxymethyl cellulose solution intragastrically respectively； one hour later， imatinib suspension was administered by oral gavage at a the dose of 10 mg/kg. Blood sample （100 μL） was taken from the orbit before and 0.5， 1， 2， 2.5， 3， 4， 5， 6， 8， 12， 24 and 36 hours after intragastric administration of imatinib. Using imatinib-d3 as internal standard， the plasma concentrations of imatinib and its metabolite N-desmethyl imatinib in rat were determined by high performance liquid chromatography-tandem mass spectrometry. The pharmacokinetic parameters were calculated by DAS 2.0 software and compared. RESULTS Compared with imatinib group， AUC0－∞ and AUMC0－∞ of imatinib in rat plasma of imatinib+medium-dose omeprazole group， cmax， t1/2， AUC0－∞ and AUMC0－∞ of imatinib in rat plasma of imatinib+high-dose omeprazole group were all increased or prolonged significantly （P＜0.05）. Compared with imatinib group， AUC0－∞ and AUMC0－∞ of N-desmethyl imatinib in rat plasma of imatinib+medium-dose omeprazole group， and cmax and AUC0→∞ of N-desmethyl imatinib in rat plasma of imatinib+high-dose omeprazole group were decreased significantly （P＜0.05）. CONCLUSIONS Omeprazole may increase the plasma concentration of imatinib in rats and reduce the plasma concentration of N-desmethyl imatinib in rats， which may be associated with inhibiting the metabolism of imatinib.