Resting metabolic rate and protein turnover in apparently healthy
elderly gambian men.
Benedek, Christine, Pierre-Yves Berclaz, Eric J[acute]equier, and Yves
Schutz.
Institut of Physiology, Faculty of Medecine, University of
Lausanne, Lausanne, Switzerland
APStracts 2:0032E, 1995.
Body composition, resting energy expenditure (REE) and whole body
protein metabolism were studied in 26 young and 28 elderly Gambian
men matched for body mass index during the dry season in a rural
village in the Gambia. REE was measured by indirect calorimetry (hood
system) in the fasting state and after five successive meals. Rates
of whole body nitrogen flux, protein synthesis and protein breakdown
were determined in the fed state from the level of isotopic
enrichment of urinary ammonia over a period of 12 hours after a
single oral dose of [15N] glycine. Expressed in absolute value, REE
was significantly lower in the elderly compared to the young group
(3.21 +/- 0.07 vs 4.04 +/- 0.07 kJ/min, p<0.0001) and when adjusted
to body weight (3.29 +/- 0.05 vs 3.96 +/- 0.05 kJ/min, p<0.0001) and
fat free mass (FFM) (3.38 +/- 0.03 vs 3.87 +/- 0.01 kJ/min,
p<0.0001). The rate of protein synthesis averaged 207 +/- 13 g
protein / day in the elderly and 230 +/- 13 g protein / day in the
young group whereas protein breakdown averaged 184 +/- 13 g protein /
day in the elderly and 203 +/- 13 g protein / day in the young group
(non significant). When values were adjusted for body weight or fat
free mass, they did not reveal any difference between the two groups.
Received 30 June 1994; accepted in final form 6 February 1995.
APS Manuscript Number E240-4.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 1 March 1995.