Affiliation: | aDepartment of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton AB, Canada T6G 2P5 bDepartment of Nutritional Science, University of Toronto, Toronto ON, Canada M5G 1X8 cDepartment of Paediatrics, University of Toronto, Toronto ON, Canada M5G 1X8 |
Abstract: | Parenteral feeding can be used to induce intestinal atrophy in piglets, and this atrophy is believed to be associated with the inability of parenterally-fed piglets to maintain arginine status via synthesis. Glucagon-like peptide 2 (GLP-2) has been shown to maintain intestinal structure and blood flow during intravenous feeding. GLP-2 infusion was hypothesized to increase the rate of endogenous arginine synthesis from proline in parenterally-fed piglets receiving an arginine deficient diet. Male piglets (n = 10, 1.5–2.0 kg), fitted with jugular vein catheters for diet and isotope infusion, and femoral vein catheters for blood sampling (d 0), were allocated to a continuous infusion of either GLP-2 (10 nmol/kg/d) or saline into the jugular vein. Piglets received 2 d of a complete diet, followed by 5 d of an arginine deficient (0.60 g/kg/d) diet. A primed, constant infusion of [guanido-14C]arginine measured arginine flux (d 6), and of [U-14C]proline (d 7) measured proline conversion to arginine. There were no differences between groups in plasma ammonia, urea and arginine concentrations and arginine flux. Piglets receiving GLP-2 had a greater jejunal mucosal mass (P = 0.003) and a two-fold greater rate of arginine synthesis from proline (P = 0.03). This study indicates that the intestinal metabolism of circulating precursors may be important for arginine synthesis in parenterally-fed neonates. |