In vivo intestinal absorption characteristics of α-hederin in rats / 中草药

ABSTRACT

Objective: To investigate the intestinal absorption characteristics of α-hederin and to explore the causes of poor bioavailability. Methods: In vivo single-pass perfusion model was used and the concentration of α-hederin was determined by HPLC. The effects of intestinal segment, drug concentration, pH value, gut microflora, and P-gp inhibitor on the intestinal absorption of the drug were investigated. Results: The absorption rate constant (Ka) of α-hederin decreased following the sequence of ileum > colon > jejunum > duodenum. Absorption parameters of α-hederin had no significant difference at different concentration of 75, 150, and 300 μg/mL and those increased with the increase of pH value. The intestinal flora which were disrupted may affect the absorption of α-hederin. There was no significant difference in Ka and Peff values between P-gp inhibitor and no P-gp inhibitor groups. Conclusion: α-Hederin can be absorbed in whole intestine, but better in lower intestine. The saturate phenomena was not observed under the test range of drug concentration, and the absorption mechanism may be the passive diffusion transport. The absorption can be better under basic condition. The absorption is significantly affected by the intestinal flora and α-hederin is not the substrate of P-gp.