The early triiodothyronine-induced changes in state IV respiration is not regulated by the proton permeability of the mitochondrial inner membrane.
The time course of changes in mitochondrial respiration, alpha-glycerophosphate dehydrogenase activity, and inner membrane proton permeability and the effects of protein synthesis inhibition was determined in hypothyroid rats treated with triiodothyronine. Respiratory rates, alpha-glycerophosphate dehydrogenase activity and proton permeability were decreased in hypothyroid rats and rose to euthyroid levels 9-12 hours after triiodothyronine treatment. Some rats received actinomycin D with the hormone to inhibit protein synthesis. Sixteen hours after actinomycin D and hormone treatment, the increases in respiratory rates and in alpha-glycerophosphate dehydrogenase activity, were completely inhibited. However, actinomycin D did not inhibit the increase in the membrane's permeability.
Horrum
M A
MA
Dept. of Internal Medicine, College of Medicine, Univ. of Nebraska Medical Center, Omaha.
Tobin
R B
RB
Ecklund
R E
RE
D000818:Animals; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D005993:Glycerolphosphate Dehydrogenase / Q000378:metabolism; D007037:Hypothyroidism / Q000378:metabolism*; D007425:Intracellular Membranes / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects*; D010539:Permeability / Q000187:drug effects; D014176:Protein Biosynthesis; D011522:Protons; D051381:Rats; D017207:Rats, Sprague-Dawley; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood / Q000494:pharmacology*
D011522:Protons; D014284:Triiodothyronine; D003609:Dactinomycin; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone; D005993:Glycerolphosphate Dehydrogenase; D013974:Thyroxine