|
|
||||||||
AJP - Endocrinology and Metabolism, Vol 257, Issue 1 E65-E73, Copyright © 1989 by American Physiological Society
ARTICLES |
S. Klein, E. J. Peters, O. B. Holland and R. R. Wolfe
Department of Internal Medicine, University of Texas Medical Branch, Galveston.
Stable isotope tracers and indirect calorimetry were used to evaluate the importance of beta-adrenergic stimulation of lipolysis and triglyceride-fatty acid cycling during fasting in healthy human volunteers. Each subject was studied after 12 and 84 h of fasting both with and without propranolol infusion (protocol 1) and when oral propranolol treatment was given throughout fasting (protocol 2). In protocol 1, the rates of appearance of glycerol and palmitic acid increased from 3.04 +/- 0.19 and 1.78 +/- 0.17 mumol.kg lean body mass-1.min-1, respectively, after 12 h of fasting to 5.28 +/- 0.31 and 3.47 +/- 0.15 mumol.kg lean body mass-1.min-1, respectively, after 84 h of fasting (P less than 0.005). The rate of triglyceride-fatty acid cycling increased from 97 +/- 8 to 169 +/- 5 mumol/min (P less than 0.005). Intravenous propranolol infusion decreased the rate of lipolysis after both 12 and 84 h of fasting, but the magnitude of the antilipolytic effect was much greater after 84 h (P less than 0.005). In protocol 2, the rate of lipolysis and triglyceride-fatty acid cycling was still increased by fasting despite beta-adrenergic blockade with oral propranolol. This study demonstrates that beta-adrenergic stimulation contributes to the mobilization of fat during fasting. However, other mechanism(s) can increase lipolysis and triglyceride-fatty acid cycling when beta-adrenergic receptors are continuously blocked.
This article has been cited by other articles:
![]() |
G. C. Henderson, J. A. Fattor, M. A. Horning, N. Faghihnia, M. L. Johnson, T. L. Mau, M. Luke-Zeitoun, and G. A. Brooks Lipolysis and fatty acid metabolism in men and women during the postexercise recovery period J. Physiol., November 1, 2007; 584(3): 963 - 981. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. F. Bernard, C. Fayolle, J.-P. Robin, and R. Groscolas Glycerol and NEFA kinetics in long-term fasting king penguins: phase II versus phase III J. Exp. Biol., September 1, 2002; 205(17): 2745 - 2754. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Mittendorfer, J. F. Horowitz, and S. Klein Gender differences in lipid and glucose kinetics during short-term fasting Am J Physiol Endocrinol Metab, December 1, 2001; 281(6): E1333 - E1339. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. F Horowitz and S. Klein Lipid metabolism during endurance exercise Am. J. Clinical Nutrition, August 1, 2000; 72(2): 558S - 563. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Zauner, B. Schneeweiss, A. Kranz, C. Madl, K. Ratheiser, L. Kramer, E. Roth, B. Schneider, and K. Lenz Resting energy expenditure in short-term starvation is increased as a result of an increase in serum norepinephrine Am. J. Clinical Nutrition, June 1, 2000; 71(6): 1511 - 1515. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. F. Horowitz, S. W. Coppack, D. Paramore, P. E. Cryer, G. Zhao, and S. Klein Effect of short-term fasting on lipid kinetics in lean and obese women Am J Physiol Endocrinol Metab, February 1, 1999; 276(2): E278 - E284. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |