Quantitative role of splanchnic region in leucine metabolism: L-(1-13C,15N)leucine and substrate balance studies

Journal Article · Sun Jul 01 00:00:00 EDT 1990 · American Journal of Physiology; (USA)

OSTI ID:6649494

Yu, Y M; Wagner, D A; Tredget, E E; Walaszewski, J A; Burke, J F; Young, V R ^[1]

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1. Shriners Burns Institute, MA (USA)

The role of the splanchnic region (Sp) in whole body leucine metabolism was assessed in six chronically catheterized fasting mongrel dogs and in eight dogs during constant enteral feeding of a complete amino acid solution (0.24 g.kg-1.h-1). We used primed continuous intravenous infusions of L-(1-13C,15N)leucine and L-(1-14C)leucine and measurements of arteriovenous isotope and leucine balance across the gut, liver, and Sp. In the fasted condition, 3.5% of arterial leucine supply was oxidized in the Sp, accounting for 13% of total body leucine oxidation, with 10% by liver. With amino acid feeding (1) leucine carbon and nitrogen fluxes and oxidation were increased (P less than 0.01) at the whole body level; (2) the percent of whole body leucine oxidation occurring in the Sp and liver increased (P less than 0.01) to 41 and 27%, respectively; (3) fractional metabolic utilization of leucine delivered to the Sp was reduced (P less than 0.01) from 47 to 35%; (4) the deamination rate of leucine in the gut was increased (P less than 0.05), along with an increased reamination rate of alpha-ketoisocaproic acid in the Sp (P less than 0.05). These findings reveal that the Sp accounts for a small fraction of whole body leucine oxidation during the fasting condition, but it plays a quantitatively important role in total body leucine oxidation during amino acid feeding; the gut and liver play cooperative roles in controlling leucine supply to peripheral tissues.

• OSTI ID: 6649494
• Journal Information: American Journal of Physiology; (USA), Vol. 259; ISSN 0002-9513
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
LEUCINE
METABOLISM
BLOOD FLOW
CARBON 13
CARBON 14 COMPOUNDS
DOGS
FASTING
INTESTINAL ABSORPTION
INTESTINES
LIVER
NITROGEN 15
TRACER TECHNIQUES
ABSORPTION
AMINO ACIDS
ANIMALS
BODY
CARBON ISOTOPES
CARBOXYLIC ACIDS
DIGESTIVE SYSTEM
EVEN-ODD NUCLEI
GASTROINTESTINAL TRACT
GLANDS
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LIGHT NUCLEI
MAMMALS
NITROGEN ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
STABLE ISOTOPES
UPTAKE
VERTEBRATES
550501* - Metabolism- Tracer Techniques