Effect of quercitrin on lactose-induced chronic diarrhoea in rats.

Quercitrin (3-rhamnosylquercetin) is a bioflavonoid contained in several crude drugs traditionally used for its antidiarrhoeal activity. The antidiarrhoeic effect of quercitrin on experimental chronic diarrhoea in rats was studied. Adult rats were fed for 14 days with a synthetic diet in which all soluble carbohydrates were substituted by lactose, resulting in chronic diarrhoea with body weight loss, colonic hyperplasia, reduced average cell size, increased alkaline phosphatase activity, increased mucus production and cytopathological alterations of the enterocyte. The rest of the animals were allowed to recover from chronic diarrhoea for 3 or 7 days, by feeding them with a standard diet, and half of them were also given quercitrin orally (50 mg/kg day). Diarrhoea ceased 48 h after lactose withdrawal, and body weight recovery was apparent after 3 days. Nevertheless, most of the alterations of the colonic mucosa persisted at that time. Quercitrin-treated rats had less diarrhoeal output and did not show mucosal hyperplasia after three days of treatment. All animals had greatly recovered by the seventh day, but histological alterations were still present, although to a lesser extent in quercitrin-treated rats. Quercitrin and related flavonoids may play a role in intestinal repair following chronic mucosal injury.