Objective: Observations showing that bile acid malabsorption is frequent in irritable bowel syndrome (IBS) suggests alterations in BA-induced secretion and absorption could contribute to IBS-associated diarrhoea. Secretory response to BA, fluid transport and bile absorption was examined in intestinal tissues from a Trichinella spiralis mouse model of post-infectious (PI) gut dysfunction in vitro. Changes in protein expression of apical sodium dependent bile acid transporter (ASBT) was also measured.
Design: T. spiralis infected mice were sacrificed at 18 and 25 days PI. Jejunal, ileal, proximal and distal colon segments were exposed to taurodeoxycholic acid or cholic acid short circuit current (SCC) increases were determined. Tritiated taurocholic acid (3H-TCA) absorption was determined in everted jejunal and ileal sacs. ASBT protein expression was determined by western blot analysis and immunohistochemistry.
Results: Basal SCC increased in ileum and distal colon at 18 and 25 days PI respectively. Ileal SCC responses to TDCA and CA were enhanced at 18 days PI. Distal colon SCC response to TDCA were raised at 18 days PI but were significantly reduced by 25 days. Ileal 3H-TCA uptake was significantly reduced at 18 and 25 day PI. Surprisingly, increased ASBT expression was observed in infected animals.
Conclusions: In a T. spiralis model of PI gut dysfunction, decreased bile absorption and enhanced secretion in response to bile acids was observed. However, decreased absorption was not due to decreased ASBT as increased expression was observed. If similar events occur in PI, the combined effects of these disturbances may contribute to some symptoms observed in PI-IBS patients.
- bile acid
- intestinal secretion
- irritbale bowel syndrome
- trichinella spiralis