ININFA   02677
INSTITUTO DE INVESTIGACIONES FARMACOLOGICAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
ILEX PARAGUARIENSIS effect on intestinal PGP activity
Autor/es:
NEIROTTI SA, NISELMAN AV, RUBIO MC,
Lugar:
Córdoba- Argentina
Reunión:
Congreso; XXXVIII reunión anual de la Asociación Argentina de Farmacología Experimental; 2006
Institución organizadora:
Asociación Argentina de Farmaocología Experimental
Resumen:
Ilex paraguariensis effect on intestinal Pgp activity 1Neirotti SA, 3Niselman AV, 1,2Rubio MC, (1)ININFA-CONICET; (2)Cát. Farmacología; (3)Cát. Matemática. FFYB, UBA. Junín 956, 1113-Bs.As., Argentina. E-mail: neirotti@ffyb.uba.ar The intestinal P-glycoprotein (Pgp), an ATP-dependent multidrug efflux pump, can be an active secretion system or an absorption barrier by transporting some drugs from intestinal cells into the lumen. Some components were reported to modulate P-glycoprotein activity. Many of herbal constituents, in particular flavonoids, have been were reported to modulate P-glycoprotein (Pgp). Pgp interacts with a broad range of substances, and limits oral drug absorption. We have analyzed the influence of mate decoctions and mate infusion on intestinal Pgp activity, considering the wide use in our society of the same one, and possible importance that it would have in the bioavailability variability that it is observed in different drugs that are substrates of this transporter. We have taken as a model to begin this study, the isolated and everted rat intestine sac. It was validated with one of its recognized substrates (3H-digoxin, 0.2mCi- 50uM) and one inhibitors (verapamil 100mM). To this end, the isolated tissues were incubated with the substrate and the efflux kinetics analyzed during 1 hour. The lineal transport was verified by liquid scintillation counter. Verapamil (100mM) inhibited the 3H-digoxin efflux by 44.3 % (p<0.001). When evaluating the effect of the decoctions of mate (2 % P/V), we observed a 44 %  inhibition of Pgp activity (p<0.001). In relation with mate infusion experiments, we also observed an inhibitory effect of  35.2 % (p<0.01) Ours results suggest that decoctions of mate and mate infusion could contribute to the variability of bioavailability of drugs that are substrates of this efflux pump.