Mucin secretion is modulated by luminal factors in the isolated vascularly perfused rat colon

BACKGROUND Mucins play an important protective role in the colonic mucosa. Luminal factors modulating colonic mucus release have been not fully identified. AIM To determine the effect of some dietary compounds on mucus discharge in rat colon. METHODS An isolated vascularly perfused rat colon model was used. Mucus secretion was induced by a variety of luminal factors administered as a bolus of 1 ml for 30 minutes in the colonic loop. Mucin release was evaluated using a sandwich enzyme linked immunosorbent assay supported by histological analysis. RESULTS The three dietary fibres tested in this study (pectin, gum arabic, and cellulose) did not provoke mucus secretion. Luminal administration of sodium alginate (an algal polysaccharide used as a food additive) or ulvan (a sulphated algal polymer) induced a dose dependent increase in mucin discharge over the concentration range 1–25 mg/l (p