Nandrolone decanoate does not enhance training effects but increases IGF-I mRNA in rat diaphragm.
To examine whether concomitant anabolic steroid treatment combined with training might enhance previously observed training effects (A. Bisschop, G. Gayan-Ramirez, H. Rollier, R. Gosselink, R. Dom, V. de Bock, and M. Decramer. Am. J. Respir. Crit. Care Med. 155: 1583-1589, 1997) and whether insulin-like growth factor I (IGF-I) was involved in these changes, male and female rats were submitted to inspiratory muscle training (IMT) for 8 wk (30 min/day, 5 times/wk) and were compared with untrained controls. During the last 5 wk of training, trained rats were divided to receive weekly either low-dose (LD; 1.5 mg/kg) or high-dose (HD; 7.5 mg/kg) nandrolone decanoate or saline for the IMT and control rats. In both sexes, diaphragm muscle mass and contractile properties were unchanged with treatment. In males, HD resulted in decreased diaphragm type I cross-sectional area (-15%; P < 0.05, HD vs. IMT), whereas no changes were observed in females. Finally, an increase in IGF-I mRNA levels was present in HD male (+73%; P < 0.05, HD vs. IMT) and female treated rats [LD (+58%) and HD (+96%) vs. IMT; P < 0.001]. We conclude that administration of nandrolone decanoate did not enhance the previously observed training effects in rat diaphragm, although it increased the IGF-I mRNA expression levels.
Gayan-Ramirez
G
G
Respiratory Muscle Research Unit, Laboratory of Pneumology, Katholieke Universiteit Leuven, B-3000 Leuven, Belgium.
Rollier
H
H
Vanderhoydonc
F
F
Verhoeven
G
G
Gosselink
R
R
Decramer
M
M
D045930:Anabolic Agents / Q000494:pharmacology*; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003964:Diaphragm / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology / Q000503:physiopathology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006321:Heart / Q000187:drug effects / Q000254:growth & development; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D018763:Muscle Fatigue; D018485:Muscle Fibers, Skeletal / Q000187:drug effects; D009277:Nandrolone / Q000031:analogs & derivatives* / Q000494:pharmacology; D000077603:Nandrolone Decanoate; D009929:Organ Size / Q000187:drug effects; D010805:Physical Conditioning, Animal / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012119:Respiration / Q000187:drug effects; D015854:Up-Regulation / Q000187:drug effects
D045930:Anabolic Agents; D012333:RNA, Messenger; D007334:Insulin-Like Growth Factor I; D009277:Nandrolone; D000077603:Nandrolone Decanoate