| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Department of Human Biology and Nutritional Sciences, University of Guelph, Guelph, Ontario N1G 2W1; Department of Medicine, McMaster University, Hamilton, Ontario, Canada L8N 3Z5; and Department of Clinical Chemistry, Huddinge University Hospital, Karolinska Institute, S-141 86 Huddinge, Sweden
This study
investigated the transformational and posttransformational control of
skeletal muscle glycogen phosphorylase and pyruvate dehydrogenase (PDH)
at three exercise power outputs [35, 65, and 90% of maximal
oxygen uptake
(
O2 max)].
Seven untrained subjects cycled at one power output for 10 min on three
separate occasions, with muscle biopsies at rest and 1 and 10 min of
exercise. Glycogen phosphorylase in the more active
(a) form was not significantly different at any time across power outputs (21.4-29.6%), with the
exception of 90%, where it fell significantly to 15.3% at 10 min. PDH
transformation increased significantly from rest (average 0.53 mmol · kg wet
muscle
1 · min1)
to 1 min of exercise as a function of power output (1.60 ± 0.26, 2.77 ± 0.29, and 3.33 ± 0.31 mmol · kg wet
muscle1 · min1
at 35, 65, and 90%, respectively) with a further significant increase
at 10 min (4.45 ± 0.35) at 90%
O2 max. Muscle
lactate, acetyl-CoA, acetylcarnitine, and free ADP, AMP, and
Pi were unchanged from rest at
35% O2 max but rose
significantly at 65 and 90%, with accumulations at 90% being
significantly higher than 65%. The results of this study indicate that
glycogen phosphorylase transformation is independent of increasing
power outputs, despite increasing glycogenolytic flux, suggesting that
flux through glycogen phosphorylase is matched to the demand for energy
by posttransformational factors, such as free
Pi and AMP. Conversely, PDH
transformation is directly related to the increasing power output and
the calculated flux through the enzyme. The rise in PDH transformation
is likely due to increased Ca2+
concentration and/or increased pyruvate. These results
demonstrate that metabolic signals related to contraction and the
energy state of the cell are sensitive to the exercise intensity and
coordinate the increase in carbohydrate use with increasing power
output.
glycogenolysis; energy state; carbohydrate; transformation; pyruvate dehydrogenase
This article has been cited by other articles:
|
|
 |
|
  C. Rantzau, M. Christopher, and F. P. Alford Contrasting effects of exercise, AICAR, and increased fatty acid supply on in vivo and skeletal muscle glucose metabolism J Appl Physiol, February 1, 2008; 104(2): 363 - 370. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. S. Bradley, G. J. F. Heigenhauser, B. D. Roy, E. M. Staples, J. G. Inglis, P. J. LeBlanc, and S. J. Peters The acute effects of differential dietary fatty acids on human skeletal muscle pyruvate dehydrogenase activity J Appl Physiol, January 1, 2008; 104(1): 1 - 9. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. J. Gurd, S. J. Peters, G. J. F. Heigenhauser, P. J. LeBlanc, T. J. Doherty, D. H. Paterson, and J. M. Kowalchuk Prior heavy exercise elevates pyruvate dehydrogenase activity and speeds O2 uptake kinetics during subsequent moderate-intensity exercise in healthy young adults J. Physiol., December 15, 2006; 577(3): 985 - 996. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. L. Talanian, R. J. Tunstall, M. J. Watt, M. Duong, C. G. R. Perry, G. R. Steinberg, B. E. Kemp, G. J. F. Heigenhauser, and L. L. Spriet Adrenergic regulation of HSL serine phosphorylation and activity in human skeletal muscle during the onset of exercise Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2006; 291(4): R1094 - R1099. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Mourtzakis, B. Saltin, T. Graham, and H. Pilegaard Carbohydrate metabolism during prolonged exercise and recovery: interactions between pyruvate dehydrogenase, fatty acids, and amino acids J Appl Physiol, June 1, 2006; 100(6): 1822 - 1830. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Stellingwerff, P. J. LeBlanc, M. G. Hollidge, G. J. F. Heigenhauser, and L. L. Spriet Hyperoxia decreases muscle glycogenolysis, lactate production, and lactate efflux during steady-state exercise Am J Physiol Endocrinol Metab, June 1, 2006; 290(6): E1180 - E1190. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. A. Roberts, S. J. G. Loxham, S. M. Poucher, D. Constantin-Teodosiu, and P. L. Greenhaff Acetyl-CoA provision and the acetyl group deficit at the onset of contraction in ischemic canine skeletal muscle Am J Physiol Endocrinol Metab, February 1, 2005; 288(2): E327 - E334. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Stellingwerff, L. Glazier, M. J. Watt, P. J. LeBlanc, G. J. F. Heigenhauser, and L. L. Spriet Effects of hyperoxia on skeletal muscle carbohydrate metabolism during transient and steady-state exercise J Appl Physiol, January 1, 2005; 98(1): 250 - 256. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. J. LeBlanc, K. R. Howarth, M. J. Gibala, and G. J. F. Heigenhauser Effects of 7 wk of endurance training on human skeletal muscle metabolism during submaximal exercise J Appl Physiol, December 1, 2004; 97(6): 2148 - 2153. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Watt, G. J. F. Heigenhauser, P. J. LeBlanc, J. G. Inglis, L. L. Spriet, and S. J. Peters Rapid upregulation of pyruvate dehydrogenase kinase activity in human skeletal muscle during prolonged exercise J Appl Physiol, October 1, 2004; 97(4): 1261 - 1267. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Bezaire, G. J. F. Heigenhauser, and L. L. Spriet Regulation of CPT I activity in intermyofibrillar and subsarcolemmal mitochondria from human and rat skeletal muscle Am J Physiol Endocrinol Metab, January 1, 2004; 286(1): E85 - E91. [Abstract] [Full Text]
|
|
|
|
|
|
H. B. Rossiter, S. A. Ward, F. A. Howe, D. M. Wood, J. M. Kowalchuk, J. R. Griffiths, and B. J. Whipp Effects of dichloroacetate on VO2 and intramuscular 31P metabolite kinetics during high-intensity exercise in humans J Appl Physiol, September 1, 2003; 95(3): 1105 - 1115. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. L. Longnus, R. B. Wambolt, H. L. Parsons, R. W. Brownsey, and M. F. Allard 5-Aminoimidazole-4-carboxamide 1-beta -D-ribofuranoside (AICAR) stimulates myocardial glycogenolysis by allosteric mechanisms Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2003; 284(4): R936 - R944. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Stellingwerff, M. J. Watt, G. J. F. Heigenhauser, and L. L. Spriet Effects of reduced free fatty acid availability on skeletal muscle PDH activation during aerobic exercise Am J Physiol Endocrinol Metab, March 1, 2003; 284(3): E589 - E596. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. Savasi, M. K. Evans, G. J. F. Heigenhauser, and L. L. Spriet Skeletal muscle metabolism is unaffected by DCA infusion and hyperoxia after onset of intense aerobic exercise Am J Physiol Endocrinol Metab, July 1, 2002; 283(1): E108 - E115. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. W. E. Rush and L. L. Spriet Skeletal muscle glycogen phosphorylase a kinetics: effects of adenine nucleotides and caffeine J Appl Physiol, November 1, 2001; 91(5): 2071 - 2078. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. U. Saunders, M. J. Watt, A. P. Garnham, L. L. Spriet, M. Hargreaves, and M. A. Febbraio No effect of mild heat stress on the regulation of carbohydrate metabolism at the onset of exercise J Appl Physiol, November 1, 2001; 91(5): 2282 - 2288. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. M. Odland, G. J. F. Heigenhauser, and L. L. Spriet Effects of high fat provision on muscle PDH activation and malonyl-CoA content in moderate exercise J Appl Physiol, December 1, 2000; 89(6): 2352 - 2358. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. L. Parolin, L. L. Spriet, E. Hultman, M. P. Matsos, M. G. Hollidge-Horvat, N. L. Jones, and G. J. F. Heigenhauser Effects of PDH activation by dichloroacetate in human skeletal muscle during exercise in hypoxia Am J Physiol Endocrinol Metab, October 1, 2000; 279(4): E752 - E761. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Kristiansen, J. Gade, J. F. P. Wojtaszewski, B. Kiens, and E. A. Richter Glucose uptake is increased in trained vs. untrained muscle during heavy exercise J Appl Physiol, September 1, 2000; 89(3): 1151 - 1158. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. C. Starritt, R. A. Howlett, G. J. F. Heigenhauser, and L. L. Spriet Sensitivity of CPT I to malonyl-CoA in trained and untrained human skeletal muscle Am J Physiol Endocrinol Metab, March 1, 2000; 278(3): E462 - E468. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. L. Parolin, L. L. Spriet, E. Hultman, M. G. Hollidge-Horvat, N. L. Jones, and G. J. F. Heigenhauser Regulation of glycogen phosphorylase and PDH during exercise in human skeletal muscle during hypoxia Am J Physiol Endocrinol Metab, March 1, 2000; 278(3): E522 - E534. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. G. Hollidge-Horvat, M. L. Parolin, D. Wong, N. L. Jones, and G. J. F. Heigenhauser Effect of induced metabolic alkalosis on human skeletal muscle metabolism during exercise Am J Physiol Endocrinol Metab, February 1, 2000; 278(2): E316 - E329. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. L. Parolin, A. Chesley, M. P. Matsos, L. L. Spriet, N. L. Jones, and G. J. F. Heigenhauser Regulation of skeletal muscle glycogen phosphorylase and PDH during maximal intermittent exercise Am J Physiol Endocrinol Metab, November 1, 1999; 277(5): E890 - E900. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. G. Hollidge-Horvat, M. L. Parolin, D. Wong, N. L. Jones, and G. J. F. Heigenhauser Effect of induced metabolic acidosis on human skeletal muscle metabolism during exercise Am J Physiol Endocrinol Metab, October 1, 1999; 277(4): E647 - E658. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. A. Howlett, G. J. F. Heigenhauser, E. Hultman, M. G. Hollidge-Horvat, and L. L. Spriet Effects of dichloroacetate infusion on human skeletal muscle metabolism at the onset of exercise Am J Physiol Endocrinol Metab, July 1, 1999; 277(1): E18 - E25. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. J. Stephens, Z.-P. Chen, B. J. Canny, B. J. Michell, B. E. Kemp, and G. K. McConell Progressive increase in human skeletal muscle AMPKalpha 2 activity and ACC phosphorylation during exercise Am J Physiol Endocrinol Metab, March 1, 2002; 282(3): E688 - E694. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. G. Richards, G. J. F. Heigenhauser, and C. M. Wood Glycogen phosphorylase and pyruvate dehydrogenase transformation in white muscle of trout during high-intensity exercise Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2002; 282(3): R828 - R836. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
