The effect of endogenous essential and nonessential fatty acids on the uptake and subsequent agonist-induced release of arachidonate

Journal Article · Sun Nov 05 04:00:00 EST 1989 · Journal of Biological Chemistry; (USA)

OSTI ID:5102535

Furth, E E; Hurtubise, V; Schott, M A; Laposata, M ^[1]

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1. Hospital of the Univ. of Pennsylvania, Philadelphia (USA)

We have demonstrated that the uptake and agonist-induced release of a pulse of arachidonate are influenced by the size and composition of preexisting endogenous fatty acid pools. EFD-1 cells, an essential fatty acid-deficient mouse fibrosarcoma cell line, were incubated with radiolabeled (14C or 3H) arachidonate, linoleate, eicosapentaenoate (EPA), palmitate, or oleate in concentrations of 0-33 microM for 24 h. After 24 h, the cells were pulsed with 0.67 microM radiolabeled (3H or 14C, opposite first label) arachidonate for 15 min and then stimulated with 10 microM bradykinin for 4 min. Because EFD-1 cells contain no endogenous essential fatty acids, we were able to create essential fatty acid-repleted cells for which the specific activity of the newly constructed endogenous essential fatty acid pool was known. Loading the endogenous pool with the essential fatty acids arachidonate, eicosapentaenoate, or linoleate (15-20 nmol of fatty acid incorporated/10(6) cells) decreased the uptake of a pulse of arachidonate from 200 to 100 pmol/10(6) cells but had no effect on palmitate uptake. The percent of arachidonate incorporated during the pulse which was released upon agonist stimulation increased 2-fold (4-8%) as the endogenous pool of essential fatty acids was increased from 0 to 15-20 nmol/10(6) cells. This 8% release was at least 3-fold greater than the percent release from the various endogenous essential fatty acid pools. In contrast, loading the endogenous pool with the nonessential fatty acids oleate or palmitate to more than 2-3 times their preexisting cellular level had no effect on the uptake of an arachidonate pulse. Like the essential fatty acids, increasing endogenous oleate increased (by 2-fold) the percent release of arachidonate incorporated during the pulse, whereas endogenous palmitate had no effect on subsequent agonist-induced release from this arachidonate pool.

• OSTI ID: 5102535
• Journal Information: Journal of Biological Chemistry; (USA), Journal Name: Journal of Biological Chemistry; (USA) Vol. 264:31; ISSN JBCHA; ISSN 0021-9258
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMAL CELLS
ANIMALS
ARACHIDONIC ACID
BIOCHEMICAL REACTION KINETICS
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
KINETICS
KININS
LABELLED COMPOUNDS
MAMMALS
MICE
MONOCARBOXYLIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PEPTIDES
POLYPEPTIDES
PROTEINS
REACTION KINETICS
RODENTS
SECRETION
TRACER TECHNIQUES
TRITIUM COMPOUNDS
TUMOR CELLS
UPTAKE
VERTEBRATES