The stimulation of tricarboxylic acid-cycle flux by alpha-adrenergic agonists in perfused rat liver.
Output of 14CO2 from 1-14C-labelled glutamate, 2-oxoglutarate or octanoate and from 4-methyl-2-oxo[2-14C]pentanoate was increased by more than 100% after infusion of phenylephrine into perfused livers of fed rats. Infusion of ethanol or sorbitol raised 3-hydroxybutyrate/acetoacetate ratios and decreased the output of 14CO2. Increases in 14CO2 output induced by phenylephrine were observed in the presence or absence of ethanol or sorbitol and were accompanied by elevated 3-hydroxybutyrate/acetoacetate ratios under all conditions examined. Phenylephrine had no effect on total tissue ATP/ADP ratios in livers from fed or starved rats. The data suggest that phenylephrine-induced increases in tricarboxylic acid-cycle flux do not arise from lowered matrix NADH/NAD+ or ATP/ADP ratios.
Taylor
W M
WM
van de Pol
E
E
Bygrave
F L
FL
D020155:3-Hydroxybutyric Acid; D000090:Acetoacetates / Q000378:metabolism; D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism; D002952:Citric Acid Cycle / Q000187:drug effects*; D000431:Ethanol / Q000494:pharmacology; D006885:Hydroxybutyrates / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D010477:Perfusion; D010656:Phenylephrine / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013012:Sorbitol / Q000494:pharmacology; D013268:Stimulation, Chemical
D000090:Acetoacetates; D006885:Hydroxybutyrates; D002245:Carbon Dioxide; D010656:Phenylephrine; D000431:Ethanol; C016635:acetoacetic acid; D013012:Sorbitol; D020155:3-Hydroxybutyric Acid