Ketogenesis in muscle: artifact or reality

Conference · Thu May 01 00:00:00 EDT 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5325673

Fink, G; Desrochers, S; Garneau, M; David, F; Landau, B R; Brunengraber, H

It has been proposed that muscle is the site of net ketogenesis. This hypothesis was based on a discrepancy between the balance of unlabeled and labeled ketone bodies across muscle beds in humans infused with (/sup 14/C)acetoacetate. It has been pointed out that the dilution of the specific activity of acetoacetate could be explained by the reversal of 3-oxoacid-CoA transferase. Catabolism of endogenous or exogenous fatty acids dilutes the specific activities of acetoacetyl-CoA and, presumably, of acetoacetate. The latter mechanism was tested in perfused working hearts and hemicorpi of rats. Organs were perfused with mM concentrations of (4-/sup 3/H)acetoacetate. The specific activities of perfusate acetoacetate and 3-hydroxybutyrate equilibrated rapidly, and then decreased 15-20% over 90 min. There was net uptake of ketone bodies. The authors conclude that (i) the data purporting to show ketogenesis in muscle can be explained by isotopic exchange between acetoacetate and acetoacetyl-CoA, and (ii) there is no net ketogenesis in muscle.

• Research Organization: Univ. of Montreal, Quebec
• OSTI ID: 5325673
• Report Number(s): CONF-8606151-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Vol. 45:6; ISSN FEPRA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETOACETATES
ANIMALS
BODY
CARBON 14 COMPOUNDS
CARBOXYLIC ACID SALTS
CARDIOVASCULAR SYSTEM
COENZYMES
ENZYME ACTIVITY
ENZYMES
HEART
ISOTOPE APPLICATIONS
KETONES
LABELLED COMPOUNDS
MAMMALS
MAN
METABOLISM
MUSCLES
ORGANIC COMPOUNDS
ORGANS
PERFUSED ORGANS
PRIMATES
RATS
RODENTS
TRACER TECHNIQUES
TRANSFERASES
TRITIUM COMPOUNDS
VERTEBRATES