Journal of Applied Physiology Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 QUICK SEARCH:   [advanced]


     


J Appl Physiol 87: 1813-1822, 1999;
8750-7587/99 $5.00
This Article
Right arrow Full Text Free
Right arrow Full Text (PDF) Free
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Gastaldelli, A.
Right arrow Articles by Wolfe, R. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Gastaldelli, A.
Right arrow Articles by Wolfe, R. R.
Vol. 87, Issue 5, 1813-1822, November 1999

Assessment of methods for improving tracer estimation of non-steady-state rate of appearance

A. Gastaldelli1,2, A. R. Coggan1, and R. R. Wolfe1

1 Metabolism Unit, Shriners Burns Institute, and University of Texas Medical Branch, Galveston, Texas 77550-2725; and 2 Institute of Clinical Physiology, National Research Council, Pisa 56100, Italy

The most common approach for estimating substrate rate of appearance (Ra) is use of the single-pool model first proposed by R. W. Steele, J. S. Wall, R. C. DeBodo, and N. Altszuler. (Am. J. Physiol. 187: 15-24, 1956). To overcome the model error during highly non-steady-state conditions due to the assumption of a constant volume of distribution (V), two strategies have been proposed: 1) use of a variable tracer infusion rate to minimize tracer-to-tracee ratio (TTR) variations (fixed-volume approach) or 2) use of two tracers of the same substrate with one infused at a constant rate and the other at a variable rate (variable-volume approach or approach of T. Issekutz, R. Issekutz, and D. Elahi. Can. J. Physiol. Pharmacol. 52: 215-224, 1974). The goal of this study was to compare the results of these two strategies for the analysis of the kinetics of glycerol and glucose under the non-steady-state condition created by a constant infusion of epinephrine (50 ng · kg-1 · min-1) with the traditional approach of Steele et al., which uses a constant infusion and fixed volume. The results showed that for glucose and glycerol the estimates of Ra obtained with the constant and the variable tracer infusion rate and the equation of Steele et al. were comparable. The variable tracer infusion approach was less sensitive to the choice of V in estimating Ra for glycerol and glucose, although the advantage of changing the tracer infusion rate was greater for glucose than for glycerol. The model of Issekutz et al. showed instability when the ratio TTR1/TTR2 approaches a constant value, and the model is more sensitive to measurement error than the constant-volume model for glucose and glycerol. We conclude that the one-tracer constant-infusion technique is sufficient in most cases for glycerol, whereas the one-tracer variable-infusion technique is preferable for glucose. Reasonable values for glucose Ra can be obtained with the constant-infusion technique if V = 145 ml/kg.

stable isotopes; epinephrine; glycerol; glucose


This article has been cited by other articles:


Home page
Am. J. Clin. Nutr.Home page
R. Roberts, A. S Bickerton, B. A Fielding, E. E Blaak, A. J Wagenmakers, M. F-F Chong, M. Gilbert, F. Karpe, and K. N Frayn
Reduced oxidation of dietary fat after a short term high-carbohydrate diet
Am. J. Clinical Nutrition, April 1, 2008; 87(4): 824 - 831.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Gastrointest. Liver Physiol.Home page
M. C. G. van de Poll, S. J. Wigmore, D. N. Redhead, R. G. H. Beets-Tan, O. J. Garden, J. W. M. Greve, P. B. Soeters, N. E. P. Deutz, K. C. H. Fearon, and C. H. C. Dejong
Effect of major liver resection on hepatic ureagenesis in humans
Am J Physiol Gastrointest Liver Physiol, November 1, 2007; 293(5): G956 - G962.
[Abstract] [Full Text] [PDF]


Home page
DiabetesHome page
R. Andrew, J. Westerbacka, J. Wahren, H. Yki-Jarvinen, and B. R. Walker
The Contribution of Visceral Adipose Tissue to Splanchnic Cortisol Production in Healthy Humans
Diabetes, May 1, 2005; 54(5): 1364 - 1370.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Endocrinol. Metab.Home page
B. Mittendorfer, D. A. Fields, and S. Klein
Excess body fat in men decreases plasma fatty acid availability and oxidation during endurance exercise
Am J Physiol Endocrinol Metab, March 1, 2004; 286(3): E354 - E362.
[Abstract] [Full Text]


Home page
J. Appl. Physiol.Home page
C. Y. Christ-Roberts, T. Pratipanawatr, W. Pratipanawatr, R. Berria, R. Belfort, and L. J. Mandarino
Increased insulin receptor signaling and glycogen synthase activity contribute to the synergistic effect of exercise on insulin action
J Appl Physiol, December 1, 2003; 95(6): 2519 - 2529.
[Abstract] [Full Text]


Home page
DiabetesHome page
B. Mittendorfer, O. Liem, B. W. Patterson, J. M. Miles, and S. Klein
What Does the Measurement of Whole-Body Fatty Acid Rate of Appearance in Plasma by Using a Fatty Acid Tracer Really Mean?
Diabetes, July 1, 2003; 52(7): 1641 - 1648.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Clin. Nutr.Home page
M. M Buijs, J. Burggraaf, C. Wijbrandts, M. L de Kam, M. Frolich, A. F Cohen, J. A Romijn, H. P Sauerwein, A E. Meinders, and H. Pijl
Blunted lipolytic response to fasting in abdominally obese women: evidence for involvement of hyposomatotropism
Am. J. Clinical Nutrition, March 1, 2003; 77(3): 544 - 550.
[Abstract] [Full Text] [PDF]


Home page
J. Clin. Endocrinol. Metab.Home page
M. M. Buijs, J. Burggraaf, J. G. Langendonk, R. C. Schoemaker, M. Frolich, J.-W. Arndt, A. F. Cohen, J. A. Romijn, M. T. Ackermans, H. P. Sauerwein, et al.
Hyposomatotropism Blunts Lipolysis in Abdominally Obese Women
J. Clin. Endocrinol. Metab., August 1, 2002; 87(8): 3851 - 3858.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Endocrinol. Metab.Home page
B. Mittendorfer, J. F. Horowitz, and S. Klein
Effect of gender on lipid kinetics during endurance exercise of moderate intensity in untrained subjects
Am J Physiol Endocrinol Metab, July 1, 2002; 283(1): E58 - E65.
[Abstract] [Full Text] [PDF]




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online