Anabolic steroids in part reverse glucocorticoid-induced alterations in rat diaphragm

• Published in: Journal of applied physiology (1985) Vol. 84; no. 5; pp. 1492 - 1499
• Main Authors: Van Balkom, Roland H. H, Dekhuijzen, P. N. Richard, Folgering, Hans T. M, Veerkamp, Jacques H, Van Moerkerk, Herman T, Fransen, Jack A. M, Van Herwaarden, Cees L. A
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Physiological Soc 01.05.1998; American Physiological Society
• Subjects: 3-Hydroxyacyl CoA Dehydrogenases - analysis; Anabolic Agents - pharmacology; Animals; Biological and medical sciences; Body Weight - drug effects; Citrate (si)-Synthase - analysis; Diaphragm - drug effects; Diaphragm - enzymology; Drug toxicity and drugs side effects treatment; Fatty Acids - metabolism; Glucocorticoids - pharmacology; Glycogen - metabolism; Male; Medical sciences; Methylprednisolone - pharmacology; Muscle Contraction - drug effects; Muscle Fibers, Skeletal - classification; Muscle Fibers, Skeletal - drug effects; Myosin Heavy Chains - classification; Nandrolone - analogs & derivatives; Nandrolone - pharmacology; Pharmacology. Drug treatments; Phosphorylases - analysis; Rats; Rats, Wistar; Respiration - drug effects; Toxicity: respiratory system, ent, stomatology; Steroid; Animal model; Rat; Respiratory disease; Toxicity; Low dose; Rodentia; Contractility; Methylprednisolone; Glucocorticoid; Long term; Vertebrata; Chemotherapy; Mammalia; Treatment; Respiratory muscle; Animal; Myosin; Diaphragm; Anabolic agent
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/jappl.1998.84.5.1492

1  Department of Pulmonary Diseases, University Hospital Nijmegen, and Departments of 2  Biochemistry and of 3  Cell Biology and Histology, University of Nijmegen, 6500 HB Nijmegen, The Netherlands Animal and clinical studies have shown respiratory muscle dysfunction caused by treatment with glucocorticoids. The present study was designed to investigate whether anabolic steroids are able to antagonize the loss of diaphragm force induced by long-term low-dose methylprednisolone (MP) administration. Male adult rats were randomized to receive saline or MP (0.2 mg · kg 1 · day 1 sc) during 9 mo, with or without nandrolone decanoate (ND; 1 mg · kg 1 · wk 1 im) during the last 3 mo. The ~10% reduction in force generation of isolated diaphragm bundles induced by MP was completely abolished by addition of ND. The MP-induced decrease in number of fibers expressing type IIb myosin heavy chains was not reversed by ND. MP slightly reduced type I, IIa, and IIx fiber cross-sectional areas (CSA), but not type IIb fiber CSA. Addition of ND abolished the reduction in IIa and IIx fiber CSA. The MP-induced alterations in glycogenolytic activity and fatty acid oxidation capacity were not reversed by ND. In conclusion, the marked reduction in diaphragm force caused by long-term low-dose MP was completely abolished by addition of ND. ND in part also antagonized the effects of MP on diaphragm morphology but showed no beneficial effects on biochemical changes. glucocorticoids; contractile properties; myosin heavy chains; biochemistry