Increased oxidative capacity in skeletal muscles from cold-acclimated ducklings: a comparison with rats.
1. The effects of prolonged cold exposure on cytochrome oxidase activity were investigated in skeletal muscles, liver and adipose tissues from cold-acclimated (CA) and control (TN) ducklings and rats. 2. Cold acclimation increased the oxidative capacity of skeletal muscles (+33% in gastrocnemius and +195% in pectoral) and liver (+47%) from CA ducklings, but decreased the oxidative capacity of gastrocnemius muscle (-22%) from CA rats. On the other hand, in these CA rats it increased the oxidative capacity of liver by 88% and, above all, brown adipose tissue by 544%. 3. The significance of these changes due to acclimation to cold in ducklings and rats is discussed. Such an increase in oxidative capacity of CA duckling muscles may explain the non-shivering thermogenesis observed in these birds.
Barré
H
H
Laboratoire de Thermorégulation et Métabolisme Energétique (U.A. 181, C.N.R.S.), Faculté de Médecine Lyon-nord, France.
Bailly
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L
Rouanet
J L
JL
D000064:Acclimatization; D002001:Adipose Tissue, Brown / Q000378:metabolism; D000818:Animals; D001835:Body Weight; D003080:Cold Temperature; D004372:Ducks / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D009132:Muscles / Q000378:metabolism*; D009929:Organ Size; D010084:Oxidation-Reduction; D051381:Rats; D011919:Rats, Inbred Strains / Q000378:metabolism
D003576:Electron Transport Complex IV