Stimulation of non-sodium-dependent water, electrolyte, and glucose transport in rat small intestine by gum arabic

In experimental models of gastroenterological disease, the soluble fiber gu m arabic (GA) acts as a proabsorptive adjuvant. This study investigated whi ch specific transport pathway(s) are affected by GA. Rat jejunum was perfus ed under anesthesia with a standardized oral rehydration solution (ORS) con taining D-glucose, with or without GA (2.5 g/liter). Tn some preparations e ither phloridizin, a competitive inhibitor of Na+-coupled D-glucose transpo rt, or phloretin, an inhibitor of basolateral glucose transport, were added to the ORS, with or without GA. Diffusion and paracellular transport chang es due to GA were evaluated with L-glucose and [C-14]polyethlyene glycol 40 00 (PEG). GA partially reversed water, Na+, and D-glucose absorption inhibi tion induced by phloridzin and normalized water and Na+ absorption ill the presence of phloretin. GA also increased absorption of water, Na+, and PEG from an L-glucose ORS. The data suggest that GA does not act via Na+ depend ent mechanism(s), but stimulates transcellular and/or transjunctional trans port pathways; therefore GA may be useful to increase absorption of solutes transported by diffusion.