The ion exchange properties of human post-mortem caecal and colonic mucus: the effect of sodium butyrate.

This study examined Na+/H+ ion exchange of caecal and colonic mucus. Two distinct Na+/H+ ion exchange populations of caecal mucus were identified, one group being a cation exchanger and the other an anion exchanger, suggesting that caecal mucus has ampholyte properties responsive to changing physical and chemical properties of luminal contents. Mucus from the colon was consistently an anionic exchanger--this may aid water and electrolyte absorption in the colon. When mucus was incubated with sodium butyrate, the Na+/H+ ion exchange properties of the mucus were decreased.