Glucose ingestion affects cardiac autonomic nervous system in
healthy subjects with different amounts of body fat.
Paolisso, Giuseppe, Daniela Manzella, Nicola Ferrara, Antonio
Gambardella, Pasquale Abete, Maria Rosaria Tagliamonte,domenico De
Lucia, Giuseppe Furgi, Costantino Picone, Salvatore Gentile, Franco
Rengo, and Michele Varricchio.
Department of Geriatric Medicine and Metabolic Diseases, Institue
of General Pathology - II University of Naples- Naples; Chair of
Geriatric Medicine - University "Federico II" - Naples-
Italy; "Salvatore Maugeri" Foundation, Institute of Campoli,
Italy
APStracts 4:0103E, 1997.
Low to high frequency ratio (LF/HF) is an indirect index of sympatho
-vagal balance derived by Heart rate spectral (HRS) analysis. We
investigate the effect of glucose ingestion on LF/HF ratio in 17
healthy, normotensive young subjects (9M/8F) with a wide body fat
content range (BF= 29+/-5.9%; range=19-42%) and a normal thyroid
hormone status. Before and after an oral glucose tolerance test
(OGTT) Holter technique and indirect calorimetry allowed to determine
heart rate and substrate oxidation in all subjects. At baseline,
LF/HF ratio correlated with BF (r= 0.60 p<0.005), waist/hip ratio
(r=0.57 p<0.01), fasting plasma insulin (r=0.55 p<0.04), leptin
(r=0.56 p<0.01) and norepinephrine (r=0.58 p<0.009)
concentrations. Age-, body fat- content and fat free mass-adjusted
respiratory quotient (r= 0.59 p<0.007) and basal metabolic rate
(r=0.61 p<0.001), were also correlated with basal LF/HF ratio.
Along with OGTT plasma glucose, insulin and norepinephrine
concentrations and basal LF/HF ratio significantly rose at 60 min and
then declined throughout the test. Area under the curve (AUC) for
LF/HF ratio correlated with BF (r= -0.66 p<0.004), fasting plasma
leptin concentration (r= -0.57 p<0.01), glucose induced
thermogenesis (r=0.62 p<0.001) and glucose uptake (r=0.59
p<0.007) and AUC for plasma norepinephrine concentration (r=0.63
p<0.001). Water instead of glucose ingestion does not significantly
affect LF/HF ratio (n=8). In conclusion, our study supports the
hypothesis that glucose ingestion affects LF/HF ratio and that such
change is related to the amount of body fat.
Received 30 October 1996; accepted in final form 1 April 1997.
APS Manuscript Number E540-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 13 May 1997