Thermoregulatory, carboxyatractylate‐sensitive uncoupling in heart and skeletal muscle mitochondria of the ground squirrel correlates with the level of free fatty acids

FEBS Letters

Brustovetsky, N.N.¹  Gogvadze, V.G.¹  Egorova, M.V.¹  Gnutov, D.Yu.¹  Skulachev, V.P.²  Mokhova, E.N.² 

[1] Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region 142292, Russia;A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119899, Russia

关键词: Thermoregulatory uncoupling;    Fatty acid;    Hibernation;    BSA;    bovine serum albumin;    CAtr;    carboxyatractylate;    DNP;    2;    4-dinitrophenol;    EDTA;    ethylenediaminetetraacetic acid;    EGTA;    [ethylenebis(oxyethylenenitrilo)]-tetraacetic acid;    HEPE-S;    N-(2-hydroxyethyl)piperazine-N′-(2-ethanesulfonic acid);   

DOI  :  10.1016/0014-5793(92)80645-W

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Thermoregulatory uncoupling of oxidative phosphorylation has been studied in heart and skeletal muscle mitochondria of ground squirrels. The respiratory rate of mitochondria in the presence of oligomycin was found to be much higher in winter (in hibernating, arousing, or aroused animals) than in summer. This additional respiration is strongly (arousing animals) or completely (hibernating and aroused animals) inhibited by carboxy-atractylate (CAtr) and bovine serum albumin (BSA). The CAtr- and BSA-induced decreases in the rate of respiration are accompanied by membrane potential increases. The rate of the CAtr- and BSA-sensitive respiration is proportional to the content of free fatty acids which, in the heart, decreases in the order: arousing > aroused = hibernating > summer animals. Maximal respiratory rates observed in the presence of dinitrophenol (arousing > aroused > summer > hibernating animals) do not parallel the fatty acid level. It is assumed that some heat production in the winter animals is due to fatty acid-induced, ATPIADP-antiporter-mediated uncoupling in heart and skeletal muscle mitochondria. The peak of heat production during arousal after hibernation also includes some other stimulatory effect on mitochondrial respiration.

【 授权许可】

Unknown