Abstract: AIM: To study the therapeutic effects of grape seed proanthocynidins extract(GSPE) on acetic acid-induced colitis in rats.METHODS: The rat colitis was induced by intracolonic enema with 10% acetic acid. Animals were divided into six groups:normal group, model group, prednisone treated group, GSPE low, medium or high dose treated group intragastrically, and GSPE or prednisone was given one time a day for seven days. The macroscopic and microscopic colon damage was scored on eighth day.The myeloperoxidase activity in colonic tissue, reflecting neutrophil infiltration was assayed by O-dianisidine method.RESULTS: The average body weight of rats obviously decreased and wet weight of damaged colon seriously increased in model group.Compared with the model group, the suppression of average body weight was obviously improved in rats treated with low or medium dose of GSPE (P <0.05) and in the contrast, the average body weight of rats treated with high dose of GSPE showed a rise trend (P <0.01).The increase of wet weight of the colon was also inhibited by different doses of GSPE (P <0.05).It was observed that there were large area ulcers and necrosis on mucous membrane of colon of rats in model group.Compared with the model group, the ulcerative area of colon mucous membrane was reduced and the mucous membrane was repaired obviously in rats treated with different doses of GSPE.Under the microscope, the large amount of inflammation exudation and necrotic tissue in colon sample was seen in model group, but the much more regenerated epithelium and gland body was observed in GSPE treated group.The results showed that the MPO activity was higher in model group than that in normal group.Compared with the model group, MPO activity in colon tissue decreased (P < 0.01).CONCLUSION: GSPE has beneficial therapeutic effect on acetic acid-induced colitis of rats in a dosedependen way.

Key words: grape seed, proanthocynidins, rats, colitis, anti-inflammation