Perfusion of the Hamster Jejunum with Conjugated and Unconjugated Bile Acids: Inhibition of Water Absorption and Effects on Morphology

Abstract

The effect of unconjugated and conjugated bile acids on water absorption and morphology of the hamster jejunum was studied by in vivo perfusion of 226 hamsters. Water absorption from control solutions, which were isotonic and simulated hamster plasma, was compared with that from identical solutions which contained 1 to 8 mm concentrations of cholic, chenodeoxycholic, or deoxycholic acids in the unconjugated form and as glycine or taurine conjugates. Dihydroxy bile acids (deoxycholic and chenodeoxycholic) inhibited water absorption and, at highest concentrations, induced fluid accumulation in the bowel. Deoxycholic acid conjugates had a similar effect, but conjugates of chenodeoxycholic acid did not; cholic acid, a trihydroxy bile acid, and its conjugates had no effect. Inhibition of absorption was reversible even though unconjugated dihydroxy bile acids produced striking structural changes of the jejunal mucosa. Bile acid conjugates caused no significant morphological changes.