Oral rehydration solutions: enhanced sodium absorption with gum arabic.

OBJECTIVE

To assess whether the addition of gum arabic (GA) to oral rehydration solutions (ORS) of either 60 or 90 mM sodium enhances net water and sodium absorption in rats.

METHODS

Perfusion of a jejunal segment of male juvenile rats under anesthesia, and determination of net water and sodium absorption, and unidirectional fluid movements using appropriate markers.

RESULTS

Addition of 5 and 10 g/L of GA increased the rates of sodium removal from the intestinal lumen perfused with ORS containing either 60 or 90 mM sodium. Net water absorption was unaffected, although GA tended to facilitate bidirectional fluid movement. The alteration of solute transport rates by the addition of 10 g/L GA was associated with an expansion of the basolateral intercellular spaces.

CONCLUSIONS

A soluble fiber such as GA appears to be an effective enhancer of sodium absorption from ORS when tested in experimental animals. Since GA does not affect viscosity, an alteration of solute diffusibility through the brush border membrane and changes in intercellular compartments may underlie the observed improvement of sodium absorption.