Measurement of non-steady-state free fatty acid turnover

Journal Article · Mon Jan 01 04:00:00 EST 1990 · American Journal of Physiology; (USA)

OSTI ID:7191481

Jensen, M D; Heiling, V; Miles, J M ^[1]

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1. Mayo Clinic, Rochester, MN (USA)

The accuracy of non-steady-state equations for measuring changes in free fatty acid rate of appearance (Ra) is unknown. In the present study, endogenous lipolysis (traced with ({sup 14}C)-linoleate) was pharmacologically suppressed in six conscious mongrel dogs. A computer-responsive infusion pump was then used to deliver an intravenous oleic acid emulsion in both constant and linear gradient infusion modes. Both non-steady-state equations with various effective volumes of distribution (V) and steady-state equations were used to measure oleate Ra (({sup 14}C)oleate). Endogenous lipolysis did not change during the experiment. When oleate Ra increased in a linear gradient fashion, only non-steady-state equations with a large (150 ml/kg) V resulted in erroneous values (9% overestimate, P less than 0.05). In contrast, when oleate Ra decreased in a similar fashion, steady-state and standard non-steady-state equations (V = plasma volume = 50 ml/kg) overestimated total oleate Ra (18 and 7%, P less than 0.001 and P less than 0.05, respectively). Overall, non-steady-state equations with an effective V of 90 ml/kg (1.8 x plasma volume) allowed the most accurate estimates of oleate Ra.

• OSTI ID: 7191481
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 258; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
BIOLOGICAL MODELS
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
DOGS
EQUATIONS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LINOLEIC ACID
MAMMALS
METABOLISM
MONOCARBOXYLIC ACIDS
OLEIC ACID
ORGANIC ACIDS
ORGANIC COMPOUNDS
TRACER TECHNIQUES
VERTEBRATES