title: Proline ameliorates arginine deficiency during enteral but not parenteral feeding in neonatal piglets.
abstract: The indispensability of arginine has not been conclusively established in newborns. Because parenteral feeding bypasses the gut (where de novo synthesis of arginine occurs from proline), a dietary supply of arginine that is sufficient to maintain urea cycle function may be of greater importance during intravenous compared with enteral feeding. Two-day-old piglets (n = 12) were fed nutritionally complete diets for 5 days via either a central vein catheter (IV pigs, n = 6) or a gastric catheter (IG pigs, n = 6). Subsequently, each piglet received three incomplete test diets [arginine free (-ARG/+PRO), proline free (-PRO/+ARG), or arginine and proline free (-ARG/-PRO)] in a randomized crossover design. Plasma ammonia was assayed every 30 min for 8 h or until hyperammonemia was observed. Ammonia increased rapidly in IV pigs receiving -ARG/+PRO and -ARG/-PRO (84 +/- 36 and 74 +/- 37 micromol. l(-1). h(-1), respectively), requiring early diet cessation. A rapid increase was also exhibited by IG pigs receiving the -ARG/-PRO, but not the -ARG/+PRO diet (31 +/- 15 vs. 11 +/- 7 micromol. l(-1). h(-1), respectively, P < 0.05). Plasma arginine and proline were indicative of deficiency (IG and IV groups) when deplete diets were infused. Arginine is indispensable in parenteral and enteral nutrition, independent of dietary proline.
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, University of Toronto, Toronto, Ontario, Canada M5G 1X8.
authors.forename: J A
authors.initials: JA
authors.lastname: Brunton
authors.forename: R F
authors.initials: RF
authors.lastname: Bertolo
authors.forename: P B
authors.initials: PB
authors.lastname: Pencharz
authors.forename: R O
authors.initials: RO
authors.lastname: Ball
mesh_terms: D000641:Ammonia / Q000097:blood; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D001120:Arginine / Q000096:biosynthesis / Q000097:blood / Q000172:deficiency*; D001284:Atrophy; D002405:Catheterization, Central Venous; D004032:Diet; D004750:Enteral Nutrition; D005774:Gastrostomy; D007275:Injections, Intravenous; D007422:Intestines / Q000473:pathology; D007441:Intubation, Gastrointestinal; D008297:Male; D010288:Parenteral Nutrition; D011392:Proline / Q000096:biosynthesis / Q000097:blood / Q000494:pharmacology*; D011498:Protein Precursors / Q000378:metabolism / Q000494:pharmacology; D013552:Swine
chemical_list: D011498:Protein Precursors; D000641:Ammonia; D001120:Arginine; D011392:Proline