Objective: To establish an everted intestinal sac method for determining absorption ingredients of yuanhuzhitong pill and study absorption characteristics of major chemical constituents of yuanhuzhitong pill.
Method: The everted intestinal sac model was adopted. Intestinal sac fluid samples at different time points after administration of three concentrations of Yuanhuzhitong pill were collected and determined by HPLC. The accumulative absorbed doses of active constituents were calculated, while the proportion between samples of yuanhuzhitong pill and absorption ingredients was compared.
Result: Eight ingredients of Yuanhuzhitong pill can be detected in intestinal sac, they are protopine, palmatine, coptisine, imperatorin, berberine, byakangelicin, alpha-allocryptopine and tetrahydropalmatine. The absorption rate constants (Ka) of eight constituents increased in jejunum and ileum with the increase in concentration of Yuanhuzhitong pill extracts (P < 0. 05), indicating a passive absorption.
Conclusion: As ingredients are selectively absorbed in intestinal sac, the everted intestinal sac method is selected to assess the intestinal absorption characteristics of ingredients of Yuanhuzhitong prescription.