Leucine metabolism in human newborns

Journal Article · Tue Dec 01 04:00:00 EST 1987 · American Journal of Physiology; (USA)

OSTI ID:7191811

Denne, S C; Kalhan, S C ^[1]

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1. Case Western Reserve Univ. School of Medicine, Cleveland, OH (USA)

The present study was designed to (1) determine whether a relationship exists between newborn birth weight and leucine metabolism and (2) compare leucine and energy metabolism in a period of rapid growth and development (i.e., newborn) with a constant nongrowth period (i.e., adult). Leucine kinetics and energy expenditure were measured in the postabsorptive state in 12 normal full-term newborns in early neonatal life and in 11 normal adults using a primed constant L-(1-{sup 13}C)leucine infusion combined with respiratory calorimetry. A significant positive correlation between newborn birth weight and leucine flux was observed. These data suggest the following. (1) A relationship exists between newborn birth weight and protein metabolism, as reflected by the correlation between leucine flux when expressed as micromoles per kilogram per hour and birth weight. (2) The high rate of leucine flux measured in newborns probably reflects the rapid remodeling of protein that occurs in this period of development, even during fasting. (3) The similar values in newborns and adults of leucine kinetics and energy expenditure when normalized to metabolic body weight and the nearly equivalent allometric exponents relating body weight to leucine flux and energy expenditure support a close relationship between leucine and energy metabolism, at least at the extremes of human growth.

• OSTI ID: 7191811
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 253:6; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADULTS
AGE GROUPS
AMINO ACIDS
BIOCHEMICAL REACTION KINETICS
CARBON 13
CARBON ISOTOPES
CARBOXYLIC ACIDS
CHILDREN
EVEN-ODD NUCLEI
FASTING
INFANTS
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LEUCINE
LIGHT NUCLEI
METABOLISM
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
REACTION KINETICS
STABLE ISOTOPES
WEIGHT