title: Clofibrate elevates enzyme activities of the tricarboxylic acid cycle in rat liver.
abstract: Activities of the tricarboxylic acid cycle enzymes were measured in subcellular fractions of liver from rats that had been fed clofibrate for 3 weeks. Large changes in these activities per gram tissue were found in the large particle fraction, which also showed an increase in total protein concentration of 76% under clofibrate treatment. The three regulatory enzymes of the cycle, namely citrate synthase, NAD(+)-linked isocitrate dehydrogenase, and 2-oxoglutarate dehydrogenase were significantly enhanced by 24% (P < 0.02), 54% (P < 0.02), and 153% (P < 0.005), respectively. Fumarase and malate dehydrogenase rose by 71% (P < 0.005) and 95% (P < 0.02), whereas succinate dehydrogenase remained unchanged. Enhancement of the citrate synthase, NAD-isocitrate dehydrogenase, and 2-oxoglutarate dehydrogenase may play a role in decreasing intracellular availability of acetyl-CoA for lipid metabolism.
authors: Department of Medical Chemistry, University of Vienna, Austria.
authors: C
authors: C
authors: Prager
authors: H J
authors: HJ
authors: Schön
authors: M
authors: M
authors: Nikfardjam
authors: D
authors: D
authors: Schmid
authors: M
authors: M
authors: Untersalmberger
authors: K
authors: K
authors: Kremser
authors: R
authors: R
authors: Kramar
mesh_terms: D000818:Animals; D002950:Citrate (si)-Synthase / Q000378:metabolism; D002952:Citric Acid Cycle; D002994:Clofibrate / Q000494:pharmacology*; D005649:Fumarate Hydratase / Q000378:metabolism; D007521:Isocitrate Dehydrogenase / Q000378:metabolism; D007655:Ketoglutarate Dehydrogenase Complex / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000201:enzymology* / Q000648:ultrastructure; D008291:Malate Dehydrogenase / Q000378:metabolism; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013347:Subcellular Fractions / Q000201:enzymology
chemical_list: D008291:Malate Dehydrogenase; D007521:Isocitrate Dehydrogenase; D007655:Ketoglutarate Dehydrogenase Complex; D002950:Citrate (si)-Synthase; D005649:Fumarate Hydratase; D002994:Clofibrate