Negative effect of clenbuterol on physical capacities and neuromuscular control of muscle atrophy in adult rats.
BACKGROUND
Clenbuterol has been used to alleviate chronic obstructive pulmonary disease and elicit an anabolic response in muscles. The aim of this study was to determine the influence of muscle mass variation on physical capacities in rats.


METHODS
The left hindlimbs of Wistar rats were immobilized for 20 days in plantarflexion with a splint and then remobilized for 16 days. The effect of a non-myotoxic dose of clenbuterol during the immobilization period was evaluated. Physical capacities were coordination, free locomotion, grip strength, and bilateral deficit.


RESULTS
Immobilization induced a loss of muscle mass, coordination, and strength without any effect on free locomotion. The positive anabolic effect of clenbuterol did not prevent a loss of physical capacities resulting from immobilization.


CONCLUSIONS
Muscle mass correlated strongly with coordination and isometric strength in untreated rats. Anabolic effect, fiber phenotype modification, and perturbation in neuromuscular communication with clenbuterol improved muscle mass, but it altered physical capacities.
ETAP-Ethologie Appliquée, 13 rue du Bois de la Champelle, 54500 Vandœuvre-lès-Nancy, France.
Guillaume
G
Lang
ETAP-Ethologie Appliquée, 13 rue du Bois de la Champelle, 54500 Vandœuvre-lès-Nancy, France.
Valerie
V
Dernoncourt
ETAP-Ethologie Appliquée, 13 rue du Bois de la Champelle, 54500 Vandœuvre-lès-Nancy, France.
Jean-François
JF
Bisson
D000704:Analysis of Variance; D000818:Animals; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D002976:Clenbuterol / Q000627:therapeutic use*; D004195:Disease Models, Animal; D005106:Exploratory Behavior; D008124:Locomotion; D008297:Male; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology*; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D053580:Muscle Strength / Q000187:drug effects / Q000502:physiology; D009133:Muscular Atrophy / Q000188:drug therapy* / Q000209:etiology / Q000534:rehabilitation*; D009469:Neuromuscular Junction / Q000187:drug effects / Q000503:physiopathology; D011597:Psychomotor Performance / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D012149:Restraint, Physical / Q000009:adverse effects; D013223:Statistics as Topic; D013997:Time Factors
D001993:Bronchodilator Agents; D002976:Clenbuterol
clenbuterol; coordination; locomotion; muscle mass; strength