| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
AJP - Endocrinology and Metabolism, Vol 264, Issue 6 E958-E965, Copyright © 1993 by American Physiological Society
ARTICLES |
P. H. McNulty, L. H. Young and E. J. Barrett
Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06510.
Whether insulin, at physiological concentrations, stimulates net muscle protein synthesis in vivo remains unresolved. To examine this, we infused either saline, insulin (2.8 mU.kg-1.min-1, euglycemic clamp), an amino acid solution, or insulin plus amino acids for 4 h into awake overnight-fasted rats. Heart and skeletal muscle protein synthesis was measured by either a continuous tracer infusion method, using L-[1-14C]leucine, L-[2,5-3H]leucine, or L-[ring-2,6-3H]phenylalanine or by injection of L-[ring-2,6-3H]phenylalanine with a pool-flooding bolus of unlabeled phenylalanine. In heart, synthesis rates obtained using the arterial plasma specific activity of [3H]phenylalanine administered as either a tracer infusion or flooding bolus were comparable in saline-treated rats (range 10.9 +/- 1.2 to 12.2 +/- 0.9%/day) and were not affected by infusion of insulin or amino acids. Estimates using continuous infusion of L-[1-14C]leucine were significantly lower (P < 0.001), except when unlabeled amino acids were given also. In skeletal muscle, rates estimated using the flooding bolus (6.7 +/- 0.8%/day) were also not affected by insulin or amino acids. Estimates using continuous infusion of [3H]leucine (2.6 +/- 0.3%/day) or [3H]phenylalanine (2.8 +/- 1.0%/day) were lower and were still lower using [14C]leucine (1.6 +/- 0.6%/day), but increased toward those estimated with the flooding bolus during amino acid infusion. We conclude that, in heart muscle of the mature rat in vivo, neither insulin nor amino acids affect protein synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)
This article has been cited by other articles:
|
|
 |
|
  G. I. Smith, D. T. Villareal, and B. Mittendorfer Measurement of human mixed muscle protein fractional synthesis rate depends on the choice of amino acid tracer Am J Physiol Endocrinol Metab, September 1, 2007; 293(3): E666 - E671. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Sheikh, G. Camejo, B. Lanne, T. Halvarsson, M. R. Landergren, and N. D. Oakes Beyond lipids, pharmacological PPAR{alpha} activation has important effects on amino acid metabolism as studied in the rat Am J Physiol Endocrinol Metab, April 1, 2007; 292(4): E1157 - E1165. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. Long, E. J. Barrett, L. Wei, and Z. Liu Adrenalectomy enhances the insulin sensitivity of muscle protein synthesis Am J Physiol Endocrinol Metab, January 1, 2003; 284(1): E102 - E109. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. M. J. O'Connor, J. A. Bush, A. Suryawan, H. V. Nguyen, and T. A. Davis Insulin and amino acids independently stimulate skeletal muscle protein synthesis in neonatal pigs Am J Physiol Endocrinol Metab, January 1, 2003; 284(1): E110 - E119. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. A. Orellana, P. M. J. O'Connor, H. V. Nguyen, J. A. Bush, A. Suryawan, M. C. Thivierge, M. L. Fiorotto, and T. A. Davis Endotoxemia reduces skeletal muscle protein synthesis in neonates Am J Physiol Endocrinol Metab, November 1, 2002; 283(5): E909 - E916. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. A. Davis, M. L. Fiorotto, D. G. Burrin, R. C. Vann, P. J. Reeds, H. V. Nguyen, P. R. Beckett, and J. A. Bush Acute IGF-I infusion stimulates protein synthesis in skeletal muscle and other tissues of neonatal pigs Am J Physiol Endocrinol Metab, October 1, 2002; 283(4): E638 - E647. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Voisin, S. Foisy, E. Giasson, C. Lambert, P. Moreau, and S. Meloche EGF receptor transactivation is obligatory for protein synthesis stimulation by G protein-coupled receptors Am J Physiol Cell Physiol, August 1, 2002; 283(2): C446 - C455. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. M.A.C. Martens, B. Demeilliers, D. Girardot, C. Daigle, H. H. Dao, D. deBlois, and P. Moreau Vessel-Specific Stimulation of Protein Synthesis by Nitric Oxide Synthase Inhibition: Role of Extracellular Signal-Regulated Kinases 1/2 Hypertension, January 1, 2002; 39(1): 16 - 21. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. A. Davis, M. L. Fiorotto, P. R. Beckett, D. G. Burrin, P. J. Reeds, D. Wray-Cahen, and H. V. Nguyen Differential effects of insulin on peripheral and visceral tissue protein synthesis in neonatal pigs Am J Physiol Endocrinol Metab, May 1, 2001; 280(5): E770 - E779. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. Dardevet, C. Sornet, M. Balage, and J. Grizard Stimulation of In Vitro Rat Muscle Protein Synthesis by Leucine Decreases with Age J. Nutr., November 1, 2000; 130(11): 2630 - 2635. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. Long, L. Saffer, L. Wei, and E. J. Barrett Amino acids regulate skeletal muscle PHAS-I and p70 S6-kinase phosphorylation independently of insulin Am J Physiol Endocrinol Metab, August 1, 2000; 279(2): E301 - E306. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. J. Fedele, J. M. Hernandez, C. H. Lang, T. C. Vary, S. R. Kimball, L. S. Jefferson, and P. A. Farrell Severe diabetes prohibits elevations in muscle protein synthesis after acute resistance exercise in rats J Appl Physiol, January 1, 2000; 88(1): 102 - 108. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. C. Vary, L. S. Jefferson, and S. R. Kimball Amino acid-induced stimulation of translation initiation in rat skeletal muscle Am J Physiol Endocrinol Metab, December 1, 1999; 277(6): E1077 - E1086. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. H. Young, Y. Renfu, X. Hu, S. Chong, S. Hasan, R. Jacob, and R. S. Sherwin Insulin-like growth factor I stimulates cardiac myosin heavy chain and actin synthesis in the awake rat Am J Physiol Endocrinol Metab, January 1, 1999; 276(1): E143 - E150. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. A. Hillier, D. A. Fryburg, L. A. Jahn, and E. J. Barrett Extreme hyperinsulinemia unmasks insulin's effect to stimulate protein synthesis in the human forearm Am J Physiol Endocrinol Metab, June 1, 1998; 274(6): E1067 - E1074. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. C. Moore, P. J. Flakoll, P.-S. Hsieh, M. J. Pagliassotti, D. W. Neal, M. T. Monohan, C. Venable, and A. D. Cherrington Hepatic glucose disposition during concomitant portal glucose and amino acid infusions in the dog Am J Physiol Endocrinol Metab, May 1, 1998; 274(5): E893 - E902. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. H. McNulty, R. J. Louard, L. I. Deckelbaum, B. L. Zaret, and L. H. Young Hyperinsulinemia Inhibits Myocardial Protein Degradation in Patients With Cardiovascular Disease and Insulin Resistance Circulation, October 15, 1995; 92(8): 2151 - 2156. [Abstract] [Full Text]
|
|
|
|
|
|
T. A. Davis, M. L. Fiorotto, D. G. Burrin, P. J. Reeds, H. V. Nguyen, P. R. Beckett, R. C. Vann, and P. M. J. O'Connor Stimulation of protein synthesis by both insulin and amino acids is unique to skeletal muscle in neonatal pigs Am J Physiol Endocrinol Metab, April 1, 2002; 282(4): E880 - E890. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
