ENHANCEMENT OF INTESTINAL WATER-ABSORPTION AND SODIUM-TRANSPORT BY GLYCEROL IN RATS

Glycerol (Gly) is a hydrophilic, absorbable, and energy-rich solute th at could make water absorption more efficient. We investigated the use of Gly in a high-energy beverage containing corn syrup (CS) by using a small intestine perfusion procedure in the rat, an approach shown ea rlier to provide good preclinical information. The effectiveness of se veral formulations with Gly and CS was compared with commercial produc ts and to experimental formulas where Gly substituted for glucose (Glc ). The CS-Gly combination was more effective than preparations on the market containing sucrose and Glc-fructose syrups (G-P and G-L, respec tively) in maintaining a net water absorption balance in the test jeju nal segment [CS-Gly = 0.021 +/- 0.226, G-L = -1.516 +/- 0.467, and G-P = -0.299 +/- 0.106 (SE) mu l . min(-1). cm(-1) (P = 0.0113)] and in r educing sodium release into the lumen [CS-Gly = -133.2 +/- 16.2, G-L = -226.7 +/- 25.2, and G-P = -245.6 +/- 23.4 nmol . min(-1) cm(-1) (P = 0.0022)]. in other preparations, at equal CS concentrations (60 and 8 0 g/l, respectively), Gly clearly improved net water absorption over a comparable Glc-containing product [CS60-Gly = 0.422 +/- 0.136 and CS8 0-Gly = 0.666 +/- 0.378 vs. CS60-Glc = -0.282 +/- 0.200 and CS80-Glc = -1.046 +/- 0.480 mu l . min(-1) cm(-1) (P = 0.0019)]. On the basis of the data of this rat intestine perfusion model, Gly could be a useful ingredient in energy-rich beverages and might enhance fluid absorptio n in humans.