anti-inflammatory effect of aqueous extract of cassia fistula in acetic acid model of colitis in rats

Considering the beneficial effects of herbal medicine in comparison with synthetic drugs and also the recommendation of iranian medical scholars on the use of cassia fistula l. in gastrointestinal inflammations, in this study the effect of aqueous extract of c. fistula fruit on the histopathological improvement of ulcerative colitis was evaluated in rats. in this study, 30 rats with a weight range of 250-300 g and about 2 months were used. ulcerative colitis was induced by acetic acid in rats, then the animals were treated orally with normal saline, sulfasalazine (360 mg/kg), or aqueous extract of c. fistula (600 and 800 mg/kg) once daily for 5 days. the animals were then sacrificed and their colons were evaluated macroscopically, histopathologically, and for myeloperoxidase (mpo) activity and weight. the severity and extent of colonic inflammation in animals receiving 400 and 800 mg/ml of c. fistula extract showed a significant decrease compared to those receiving normal saline (p< 0.05). a decrease in colon weight was observed in the group of animals receiving a concentration of 800 mg/ml of the extract. c. fistula aqueous extract did not show any effect in reducing the activity of the mpo enzyme.