Effects of inhibition of. beta. -oxidation on tissue kinetics of C-11 palmitate in normal myocardium

Conference · Wed May 01 04:00:00 EDT 1985 · J. Nucl. Med.; (United States)

OSTI ID:5941571

Wijns, W; Schwaiger, M; Huang, S C; Selin, C; Grover-McKay, M; Hansen, H; Phelps, M; Schelbert, H R

C-11 palmitate (CPA) clears from myocardium biexponentially. The late slow tissue clearance curve component is thought to represent tracer deposited in the endogenous lipid pool. The early rapid component is thought to be related to oxidation of CPA. The nature of the curve components can be clarified by specific inhibition of individual metabolic steps, e.g., ..beta..-oxidation. Therefore, 11 dogs were studied at control and again after inhibition of carnitine acyltransferase I with iv. tetradecylglycidic acid (TDGA; 10 mg/kg). CPA was injected into the coronary circulation. Myocardial time activity curves (TAC) were analyzed by least square fitting. After TDGA, the late slow phase was unchanged (RS=32 +- 9%; T=336 +- 146 min) but the early rapid phase was reduced (RS=18 +- 8%; T=2.9 +- 1.4 min) while 50 +- 9% of extracted CPA diffused back (T=10.8 +- 3.6 sec). Thus, inhibition of ..beta..-oxidation shifted substrate usage from FFA to carbohydrates, had no effect on esterification of CPA but enhanced its back diffusion from myocardium. As discussed in this paper the decline of the early rapid phase indicates its relationship to CPA oxidation.

• Research Organization: UCLA School of Medicine, Los Angeles, CA
• OSTI ID: 5941571
• Report Number(s): CONF-850611-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 26:5
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
550601 -- Medicine-- Unsealed Radionuclides in Diagnostics
59 BASIC BIOLOGICAL SCIENCES
62 RADIOLOGY AND NUCLEAR MEDICINE
ALDEHYDES
ANIMALS
ANTIMETABOLITES
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BIOLOGICAL PATHWAYS
BODY
CARBOHYDRATES
CARBON 11
CARBON ISOTOPES
CARBOXYLIC ACIDS
CARDIOVASCULAR SYSTEM
CHEMICAL REACTIONS
COUNTING TECHNIQUES
DIAGNOSTIC TECHNIQUES
DIAGNOSTIC USES
DISTRIBUTION
DOGS
DRUGS
ENZYME INHIBITORS
ENZYMES
EVEN-ODD NUCLEI
FLUORODEOXYGLUCOSE
FUNCTIONS
GLUCOSE
HEART
HEXOSES
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED POOL TECHNIQUES
LABELLING
LEAST SQUARE FIT
LIGHT NUCLEI
MAMMALS
MAXIMUM-LIKELIHOOD FIT
METABOLISM
MINUTES LIVING RADIOISOTOPES
MONOCARBOXYLIC ACIDS
MONOSACCHARIDES
MUSCLES
MYOCARDIUM
NUCLEI
NUMERICAL SOLUTION
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
OXIDATION
RADIOISOTOPE SCANNING
RADIOISOTOPES
RADIONUCLIDE KINETICS
RETENTION FUNCTIONS
SACCHARIDES
SCINTISCANNING
TISSUE DISTRIBUTION
TRACER TECHNIQUES
TRANSFERASES
USES
VERTEBRATES