Muscle-specific up-regulation of rat UCP3 mRNA expression by long-term hindlimb unloading.
The effect of long-term hindlimb unloading (2 or 5 week) on the expression of uncoupling protein-3 (UCP3) gene was investigated in rat skeletal muscles. The interaction of hindlimb unloading and thyroid status was also investigated at 2 weeks. Whatever the duration, mechanical unloading induced a similar increase in UCP3 mRNA relative abundance in the slow-twitch soleus (SOL) muscle (+80%, P < 0.05), whereas no effect was observed in the fast-twitch extensor digitorum longus (EDL) muscle. Hypothyroidism down-regulated while hyperthyroidism up-regulated UCP3 mRNA relative abundance in both SOL and EDL muscles, but thyroid status did not prevent the up-regulation of UCP3 induced by 2 weeks of suspension. These data therefore indicate for the first time that long-term hindlimb unloading up-regulates muscle UCP3 gene expression in a muscle-specific manner which is independent of thyroid status.
Denjean
F
F
Cellulaires et Moléculaires, UMR 5578 CNRS-Université Cl. Bernard Lyon I, 43 Boulevard du 11 Novembre 1918, Villeurbanne, F-69622, France.
Desplanches
D
D
Lachuer
J
J
Cohen-Adad
F
F
Mayet
M H
MH
Duchamp
C
C
D000818:Animals; D002352:Carrier Proteins / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics; D006614:Hindlimb; D006980:Hyperthyroidism / Q000235:genetics; D007037:Hypothyroidism / Q000235:genetics; D007473:Ion Channels; D024101:Mitochondrial Proteins; D018482:Muscle, Skeletal / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013312:Stress, Physiological / Q000378:metabolism; D000071247:Uncoupling Protein 3
D002352:Carrier Proteins; D007473:Ion Channels; D024101:Mitochondrial Proteins; D012333:RNA, Messenger; C000604394:Ucp3 protein, rat; D000071247:Uncoupling Protein 3