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), Vol. 45:6; Conference: 76. annual meeting of the Federation of American Society for Experimental Biology, Washington, DC, USA, 8 Jun 1986
• Country of Publication: United States
• Language: English

Related Subjects

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