Previous studies have confirmed the improved tolerance of a
peptide enteral compared to standard enteral alimentation in hypoalbuminemic,
critically ill patients. Animal studies, including hypoproteinemic, volume-expanded rats, demonstrated that the
protein hydrolysate of a
peptide enteral formula was responsible for the enhanced absorption. The purpose of this study was to determine whether the composition of small MW
peptides (
protein hydrolysate) in two commercially available
peptide enteral formulas would affect the rate of intestinal absorption and
albumin clearance in intact jejunal loops before and during
hypoproteinemia induced by iv infusion of
Tyrode's solution in Sprague-Dawley rats. Net transmucosal water movement was calculated using a volume recovery method;
albumin clearance was calculated using iv radiolabeled
albumin. We studied three groups of animals during
luminal perfusion with either
Tyrode's solution, diet A containing 21%
peptides, or diet B containing 56%
peptides. When compared to
luminal perfusion with
Tyrode's solution (control animals), both diets significantly enhanced net transmucosal water absorption before volume expansion (p less than .05). With the induction of
hypoproteinemia, diet B continued to stimulate water absorption when compared to control animals (p less than .01).
Luminal perfusion with diet A failed to attenuate net water secretion induced by
hypoproteinemia. Capillary and mucosal
albumin clearance was similar for all groups studied. These findings suggest the percentage of small MW
peptides may affect the rate of intestinal absorption in patients with acute
kwashiorkor-like
hypoalbuminemia.