Abstract: AIM: To explore the transport and deliv-ery of active drug from dexamethasone-angelica sinensis polysaccharides prodrug in the gastrointestinal tract of rats.METHODS: Dexamethasone and the prodrug were orally administered to rats at the dose of 1.96 mg·kg^-1 (calculated by carried dexamethasone).The drugs in the plasma and contents of different parts of the rats' gastroi-ntestinal tract were determined by high performance liquid chromatography (HPLC).RESULTS: Dexamethasone carried by the prodrug wasmainly released in the contents andmucosa of cecum and colon after oral administration of the prodrug.The absorption of released dexamethasone was reduced significantly.The peak time, peak concen-tration and AUC were 7.2 h, 42 μg·L^-1 and 334 μg·h·L^-1, respectively.However, free dexamethasone was found mainly in the contents and mucosa of the stom-ach, proximal and distal small intestine after oral admin-istration.The peak time, peak concentration and AUC were 2.2 h, 2 120 μg·L^-1 and 11 875 μg·h·L^-1, re-spectively.CONCLUSION: Dexamethasone can be spe-cifically delivered to the cecum and colon by using dexam-ethasone-angelica sinensis polysaccharides prodrug.The absorption of dexamethasone was reduced significantly and the drug concentration in colon was increased significant-ly.The prodrug has a potential in the treatment of colitis.

Key words: colon-targeted delivery system, pro-drug, dexamethasone, angelica sinensis polysaccharides, colitis