| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Articles in PresS, published online ahead of print October 22, 2001
Am J Physiol Endocrinol Metab, 10.1152/ajpendo.00191.2001
Submitted on May 1, 2001
Accepted on October 5, 2001
1 Medicine/Pulmonary Division, Cedars-Sinai Medical Center/UCLA School of Medicine, Los Angeles, CA, USA
2 Medicine/Endocrinology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
* To whom correspondence should be addressed. E-mail: michael.lewis{at}cshs.org.
Recent studies suggest that the anabolic effects of testosterone in muscle may in part be mediated by the insulin-like growth factor (IGF) system. The aim of this study was to examine the effects of nandrolone (NAN) on both IGF-1 and IGF binding proteins (BP) in the diaphragm muscle of one-year old female rats. NAN (6.6 mg/kg/day) was infused continuously for 17 days using a subcutaneous silastic implant, while controls (CTL) received blank capsules. Muscle fibers were classified immunohistochemically, and fiber cross-sectional areas (CSA) determined quantitatively. IGF-1 levels in both serum and muscle were determined by radioimmunoassay. Immunoreactivity to an IGF-1 antibody was used to localize IGF-1 expression within individual muscle fibers. Muscle IGFBPs were determined by SDS-PAGE and Western ligand blotting and measured by scanning densitometry. Body weight was higher in the NAN group compared to CTL (9.4 ± 4.5% vs. -0.6 ± 3.1%). There were no changes in the fiber composition of the diaphragm. NAN increased the CSA of type IIa (20%) and type IIx/b (30%) diaphragm fibers. Levels of IGF-1 in the diaphragm muscle were significantly higher (50%) in NAN treated animals. Immunohistochemistry revealed increased localization of IGF-1 within type IIx/b diaphragm fibers. In addition, NAN increased IGFBP-3 within the diaphragm (69%) while IGFBP-4 decreased (40%). We conclude that NAN-induced diaphragm muscle fiber hypertrophy is in part mediated by influences of the IGF system within the muscle, such that coordinated changes in IGFBPs reflect a direction of change that has been associated with an anabolic response in other test systems.
This article has been cited by other articles:
|
|
 |
|
  M. S. Pampusch, M. E. White, M. R. Hathaway, T. J. Baxa, K. Y. Chung, S. L. Parr, B. J. Johnson, W. J. Weber, and W. R. Dayton Effects of implants of trenbolone acetate, estradiol, or both, on muscle insulin-like growth factor-I, insulin-like growth factor-I receptor, estrogen receptor-{alpha}, and androgen receptor messenger ribonucleic acid levels in feedlot steers J Anim Sci, December 1, 2008; 86(12): 3418 - 3423. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. R. Dayton and M. E. White Cellular and molecular regulation of muscle growth and development in meat animals J Anim Sci, April 1, 2008; 86(14_suppl): E217 - E225. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. I. Lewis, M. Fournier, T. W. Storer, S. Bhasin, J. Porszasz, S.-G. Ren, X. Da, and R. Casaburi Skeletal muscle adaptations to testosterone and resistance training in men with COPD J Appl Physiol, October 1, 2007; 103(4): 1299 - 1310. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. A. C. Ottenheijm, G. J. Jenniskens, M. C. P. Geraedts, T. Hafmans, L. M. A. Heunks, T. H. van Kuppevelt, and P. N. R. Dekhuijzen Diaphragm dysfunction in chronic obstructive pulmonary disease: a role for heparan sulphate? Eur. Respir. J., July 1, 2007; 30(1): 80 - 89. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A M Solomon and P M G Bouloux Modifying muscle mass - the endocrine perspective. J. Endocrinol., November 1, 2006; 191(2): 349 - 360. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. I. Lewis, M. Fournier, X. Da, H. Li, Z. Mosenifar, R. J. McKenna Jr, and A. H. Cohen Short-term Influences of Lung Volume Reduction Surgery on the Diaphragm in Emphysematous Hamsters Am. J. Respir. Crit. Care Med., October 1, 2004; 170(7): 753 - 759. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. S. Pampusch, B. J. Johnson, M. E. White, M. R. Hathaway, J. D. Dunn, A. T. Waylan, and W. R. Dayton Time course of changes in growth factor mRNA levels in muscle of steroid-implanted and nonimplanted steers J Anim Sci, November 1, 2003; 81(11): 2733 - 2740. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. I. Lewis, H. Li, Z.-S. Huang, M. S. Biring, B. Cercek, and M. Fournier Influence of varying degrees of malnutrition on IGF-I expression in the rat diaphragm J Appl Physiol, August 1, 2003; 95(2): 555 - 562. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Fournier, Z.-S. Huang, H. Li, X. Da, B. Cercek, and M. I. Lewis Insulin-like growth factor I prevents corticosteroid-induced diaphragm muscle atrophy in emphysematous hamsters Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2003; 285(1): R34 - R43. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. E. Spangenburg, T. Abraha, T. E. Childs, J. S. Pattison, and F. W. Booth Skeletal muscle IGF-binding protein-3 and -5 expressions are age, muscle, and load dependent Am J Physiol Endocrinol Metab, February 1, 2003; 284(2): E340 - E350. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
