AJP - Regu Track the topics, authors and articles important to you
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Regul Integr Comp Physiol 264: R797-R803, 1993;
0363-6119/93 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
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 Weber, J. M.
Right arrow Articles by Taylor, C. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Weber, J. M.
Right arrow Articles by Taylor, C. R.

AJP - Regulatory, Integrative and Comparative Physiology, Vol 264, Issue 4 797-R803, Copyright © 1993 by American Physiological Society

ARTICLES

Mismatch between lipid mobilization and oxidation: glycerol kinetics in running African goats

J. M. Weber, T. J. Roberts and C. R. Taylor
Concord Field Station, Museum of Comparative Zoology, Harvard University, Cambridge Massachusetts 02138.

Glycerol kinetics and total fatty acid (FA) oxidation of trained African pygmy goats were measured by continuous infusion of [2-3H]glycerol and indirect calorimetry during treadmill exercise at 40, 60, and 85% maximal O2 consumption (VO2max). Our main goals were 1) to determine whether rates of FA mobilization and utilization are eventually matched as exercise intensity increases, thereby minimizing reesterification to supply more FA to working muscles, and 2) to test the hypothesis that lipolytic rate is proportional to aerobic capacity by comparing low-aerobic goats with published values from highly aerobic dogs and humans. Mean rate of glycerol release in the circulation (Ra glycerol) was 3.83 +/- 0.11 at rest, 7.69 +/- 0.88 at 40% VO2max, reached a maximum of 15.32 +/- 0.95 at 60% VO2max, and returned to 10.53 +/- 0.76 mumol.kg-1 x min-1 at 85% VO2max. Lipolytic rate did not match total FA oxidation, implying that Ra glycerol cannot be used as an index of FA utilization, even during intense exercise. A large fraction of total FA released by lipolysis was reesterified at 60 and 85% VO2max, showing that FA mobilization does not limit whole animal FA oxidation at these intensities. Comparing goat, dog, and human responses reveals that mammalian lipolytic rate is scaled with aerobic capacity. High- and low-aerobic species exercising at the same %VO2max mobilize FA in exact proportion with their metabolic rate, suggesting that the relative contribution of FA to total energy provision is independent of VO2max.


This article has been cited by other articles:


Home page
 J. Exp. Biol.Home page
L. Magnoni, E. Vaillancourt, and J.-M. Weber
In vivo regulation of rainbow trout lipolysis by catecholamines
J. Exp. Biol., August 1, 2008; 211(15): 2460 - 2466.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
G. B. McClelland, P. W. Hochachka, S. P. Reidy, and J.-M. Weber
High-altitude acclimation increases the triacylglycerol/fatty acid cycle at rest and during exercise
Am J Physiol Endocrinol Metab, September 1, 2001; 281(3): E537 - E544.
[Abstract] [Full Text] [PDF]


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