RESUMEN
Arsenite is an important heavy metal. Some Chinese traditional medicines contain significant amounts of arsenite. The aim of this study was to investigate subacute exposure of arsenite on activities of cytochrome P450 enzymes and pharmacokinetic behaviors of drugs in rats. Midazolam, tolbutamide, metoprolol, omeprazole, caffeine, and chlorzoxazone, the probe substrates for cytochrome P450 (CYP) s3A, 2C6, 2D, 2C11, 1A, and 2E, were selected as probe drugs for the pharmacokinetic study. Significant decreases in areas under the curves of probe substrates were observed in rats after consecutive 30-day exposure to As at 12 mg/kg. Microsomal incubation study showed that the subacute exposure to arsenite resulted in little change in effects on the activities of P450 enzymes examined. However, everted gut sac study demonstrated that such exposure induced significant decreases in intestinal absorption of these drugs by both passive diffusion and carrier-mediated transport. In addition, in vivo study showed that the arsenite exposure decreased the rate of peristaltic propulsion. The decreases in intestinal permeability of the probe drugs and peristaltic propulsion rate most likely resulted in the observed decreases in the internal exposure of the probe drugs. Exposure to arsenite may lead to the reduction of the efficiencies of pharmaceutical agents coadministered resulting from the observed drug-drug interactions. SIGNIFICANCE STATEMENT: Exposure to arsenite may lead to the reduction of the efficiencies of pharmaceutical agents coadministered resulting from the observed drug-drug interactions. The present study, we found that P450 enzyme probe drug exposure was reduced in arsenic-exposed animals (areas under the curve) and the intestinal absorption of the drug was reduced in the animals. Subacute arsenic exposure tends to cause damage to intestinal function, which leads to reduced drug absorption.
Asunto(s)
Arsenitos , Sistema Enzimático del Citocromo P-450 , Interacciones Farmacológicas , Ratas Sprague-Dawley , Animales , Arsenitos/toxicidad , Arsenitos/farmacocinética , Masculino , Ratas , Sistema Enzimático del Citocromo P-450/metabolismo , Absorción Intestinal/efectos de los fármacos , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Omeprazol/farmacología , Omeprazol/farmacocinética , Midazolam/farmacocinética , Cafeína/farmacocinética , Clorzoxazona/farmacocinética , Metoprolol/farmacocinética , Metoprolol/farmacología , Tolbutamida/farmacocinética , Compuestos de Sodio/toxicidad , Compuestos de Sodio/farmacocinéticaRESUMEN
El estudio del tipo de interacción involucrada en la formación de dispersiones sólidas de tolbutamida con distintas proporciones de acetamida y propianamida, ha requerido del diseño y validación de un método analítico por cromatografía líquida de alta eficacia (CLAE) que permita cuantificar la proporción de los transportadores en mezclas físicas y en dispersión sólida. El método resultó ser lineal, preciso y exacto en el intervalo de concentración de 100-1,56 µg/mL para tolbutamida y 50-0,781 µg/mL para acetamida y propianamida (AU)