Hypoproteinemia-induced mucosal albumin leakage. Influence of luminal nutrients.

Previous studies indicate that a peptide enteral formula significantly attenuates the intestinal water and albumin loss in volume-expanded rats with acute hypoproteinemia. The purpose of this study was to determine the relative abilities of the fat, carbohydrate, and protein components of the peptide enteral formula to stimulate water absorption and attenuate albumin turnover in intact jejunal segments during hypoproteinemia induced by intravenous infusion of Tyrode's solution (2.5 ml/min/kg) in Sprague-Dawley rats. Radio iodinated albumin movement from blood to lumen was used to estimate mucosal albumin clearance. Net transmucosal water was measured using a volume recovery method. When compared to luminal perfusion with Tyrode's solution (control animals), protein (as a protein hydrolysate) or protein combined with fat significantly enhanced fluid absorption (P less than 0.05) before and during volume expansion. This did not occur with carbohydrates or when carbohydrate was combined with the protein hydrolysate. However, the hypoproteinemia-induced increase in mucosal albumin clearance was significantly (P less than 0.05) attenuated by all solutions containing the carbohydrate component of the diet. These findings indicate that the protein component of the enteral formula is responsible for the enhanced net transmucosal water movement in hypoproteinemic animals. However, the carbohydrate component is largely responsible for the decrease in intestinal albumin clearance.