The pH-dependent reciprocal changes in contributions of ADP/ATP antiporter and aspartate/glutamate antiporter to the fatty acid-induced uncoupling.
The pH effect on carboxyatractylate-, glutamate- and aspartate-induced recoupling of palmitate-uncoupled rat liver mitochondria has been studied. Stimulation of respiration by low palmitate concentrations (5-20 microM) in the presence of 3 mM MgCl2 is shown to be pH-independent within the 7.0-7.8 range. The recoupling effect of glutamate (or aspartate) decreases and that of carboxyatractylate increases with increase in pH. The recoupling effect of a combination of carboxyatractylate and glutamate (aspartate) appears to be constant at these pH values, being as high as about 80%. It is concluded that uncoupling by low palmitate in liver mitochondria is mediated mainly by ATP/ADP and aspartate/glutamate antiporter.
Samartsev
V N
VN
Mari State University, Yoshkar-Ola, Russia.
Mokhova
E N
EN
Skulachev
V P
VP
D000818:Animals; D017920:Antiporters / Q000378:metabolism*; D001224:Aspartic Acid / Q000494:pharmacology; D001278:Atractyloside / Q000031:analogs & derivatives / Q000494:pharmacology; D005227:Fatty Acids / Q000494:pharmacology*; D018698:Glutamic Acid / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D015636:Magnesium Chloride / Q000494:pharmacology; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism*; D000226:Mitochondrial ADP, ATP Translocases / Q000378:metabolism*; D010101:Oxygen Consumption; D019308:Palmitic Acid / Q000494:pharmacology; D051381:Rats; D014475:Uncoupling Agents / Q000494:pharmacology*
D017920:Antiporters; D005227:Fatty Acids; D014475:Uncoupling Agents; D015636:Magnesium Chloride; D001278:Atractyloside; D019308:Palmitic Acid; D001224:Aspartic Acid; D018698:Glutamic Acid; D000226:Mitochondrial ADP, ATP Translocases; C003853:carboxyatractyloside