Carboxyatractylate-sensitive uncoupling in liver mitochondria from ground squirrels during hibernation and arousal.
Energy coupling parameters of liver mitochondria from hibernating and arousing ground squirrels have been studied. In the oligomycin-treated mitochondria, carboxyatractylate, an inhibitor of the ATP/ADP-antiporter, is shown to decrease the respiration rate, to increase the membrane potential and to lower the rate of the membrane-potential discharge after the addition of cyanide to liver mitochondria from hibernating and arousing animals. BSA effectively substitutes for carboxyactactylate so that carboxyactactylate, added after BSA, has no effect. In mitochondria from hibernating animals, the maximal respiration rate in the presence of DNP and the rate of the membrane potential discharge in its absence are much lower than in those from arousing animals. It has been concluded that upon arousal of the animals from hibernation, the uncoupling of oxidative phosphorylation, mediated by free fatty acids and ATP/ADP-antiporter, parallels the respiratory chain activation.
Brustovetsky
N N
NN
Institute of Biological Physics, USSR Academy of Sciences, Pushchino, Moscow Region.
Amerkanov
Z G
ZG
Yegorova
M E
ME
Mokhova
E N
EN
Skulachev
V P
VP
D019297:2,4-Dinitrophenol; D000818:Animals; D001143:Arousal / Q000502:physiology*; D001278:Atractyloside / Q000031:analogs & derivatives* / Q000494:pharmacology; D004140:Dinitrophenols / Q000494:pharmacology; D005230:Fatty Acids, Nonesterified / Q000494:pharmacology; D006605:Hibernation / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism*; D000226:Mitochondrial ADP, ATP Translocases / Q000037:antagonists & inhibitors / Q000502:physiology; D009840:Oligomycins / Q000494:pharmacology; D010085:Oxidative Phosphorylation / Q000187:drug effects*; D010101:Oxygen Consumption / Q000187:drug effects; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000494:pharmacology; D012589:Sciuridae / Q000378:metabolism*; D012710:Serum Albumin, Bovine / Q000494:pharmacology
D004140:Dinitrophenols; D005230:Fatty Acids, Nonesterified; D009840:Oligomycins; D010169:Palmitic Acids; D001278:Atractyloside; D012710:Serum Albumin, Bovine; D019308:Palmitic Acid; D000226:Mitochondrial ADP, ATP Translocases; D019297:2,4-Dinitrophenol; C003853:carboxyatractyloside