Effects of medium fatty acid concentration, epinephrine, and glucose on palmitate-l-C14 oxidation and incorporation into neutral lipids by skeletal muscle in vitro

The rate of oxidation of palmitate-l-C14 to C14O2 by rat skeletal muscle in vitro was shown to increase markedly as a function of the concentrations of free fatty acids (FFA) in the medium. Neither epinephrine nor glucose had any important effect. The rate of incorporation of palmitate-l-C14 into ti...

Full description

Bibliographic Details
Main Authors: Philip Eaton, Daniel Steinberg
Format: Article
Language:English
Published: Elsevier 1961-10-01
Series:Journal of Lipid Research
Online Access:http://www.sciencedirect.com/science/article/pii/S0022227520404821
_version_ 1818925565058482176
author Philip Eaton
Daniel Steinberg
author_facet Philip Eaton
Daniel Steinberg
author_sort Philip Eaton
collection DOAJ
description The rate of oxidation of palmitate-l-C14 to C14O2 by rat skeletal muscle in vitro was shown to increase markedly as a function of the concentrations of free fatty acids (FFA) in the medium. Neither epinephrine nor glucose had any important effect. The rate of incorporation of palmitate-l-C14 into tissue neutral lipids was also increased by higher levels of FFA in the medium. At any given concentration of FFA this incorporation was also increased by glucose but was not altered by epinephrine. It is concluded that the deposition of triglyceride reported to occur in muscle after epinephrine or norepinephrine administration is due to the effects of these hormones on serum FFA levels and not to a direct effect on muscle metabolism. The profound effect of FFA concentration on the rate of FFA oxidation suggests that regulation of the serum concentrations of this labile lipid fraction may be of central importance in determining over-all rates of body metabolism. In particular, it is proposed that the elevated metabolic rates after epinephrine administration and in hyperthyroidism may, in part, be directly attributable to the elevations of serum FFA in these conditions.
first_indexed 2024-12-20T02:43:14Z
format Article
id doaj.art-03941d5a11e446328c6411a949df57b1
institution Directory Open Access Journal
issn 0022-2275
language English
last_indexed 2024-12-20T02:43:14Z
publishDate 1961-10-01
publisher Elsevier
record_format Article
series Journal of Lipid Research
spelling doaj.art-03941d5a11e446328c6411a949df57b12022-12-21T19:56:14ZengElsevierJournal of Lipid Research0022-22751961-10-0124376382Effects of medium fatty acid concentration, epinephrine, and glucose on palmitate-l-C14 oxidation and incorporation into neutral lipids by skeletal muscle in vitroPhilip Eaton0Daniel Steinberg1Laboratory of Cellular Physiology and Metabolism, National Heart Institute, National Institutes of Health, Bethesda 14, MarylandLaboratory of Cellular Physiology and Metabolism, National Heart Institute, National Institutes of Health, Bethesda 14, MarylandThe rate of oxidation of palmitate-l-C14 to C14O2 by rat skeletal muscle in vitro was shown to increase markedly as a function of the concentrations of free fatty acids (FFA) in the medium. Neither epinephrine nor glucose had any important effect. The rate of incorporation of palmitate-l-C14 into tissue neutral lipids was also increased by higher levels of FFA in the medium. At any given concentration of FFA this incorporation was also increased by glucose but was not altered by epinephrine. It is concluded that the deposition of triglyceride reported to occur in muscle after epinephrine or norepinephrine administration is due to the effects of these hormones on serum FFA levels and not to a direct effect on muscle metabolism. The profound effect of FFA concentration on the rate of FFA oxidation suggests that regulation of the serum concentrations of this labile lipid fraction may be of central importance in determining over-all rates of body metabolism. In particular, it is proposed that the elevated metabolic rates after epinephrine administration and in hyperthyroidism may, in part, be directly attributable to the elevations of serum FFA in these conditions.http://www.sciencedirect.com/science/article/pii/S0022227520404821
spellingShingle Philip Eaton
Daniel Steinberg
Effects of medium fatty acid concentration, epinephrine, and glucose on palmitate-l-C14 oxidation and incorporation into neutral lipids by skeletal muscle in vitro
Journal of Lipid Research
title Effects of medium fatty acid concentration, epinephrine, and glucose on palmitate-l-C14 oxidation and incorporation into neutral lipids by skeletal muscle in vitro
title_full Effects of medium fatty acid concentration, epinephrine, and glucose on palmitate-l-C14 oxidation and incorporation into neutral lipids by skeletal muscle in vitro
title_fullStr Effects of medium fatty acid concentration, epinephrine, and glucose on palmitate-l-C14 oxidation and incorporation into neutral lipids by skeletal muscle in vitro
title_full_unstemmed Effects of medium fatty acid concentration, epinephrine, and glucose on palmitate-l-C14 oxidation and incorporation into neutral lipids by skeletal muscle in vitro
title_short Effects of medium fatty acid concentration, epinephrine, and glucose on palmitate-l-C14 oxidation and incorporation into neutral lipids by skeletal muscle in vitro
title_sort effects of medium fatty acid concentration epinephrine and glucose on palmitate l c14 oxidation and incorporation into neutral lipids by skeletal muscle in vitro
url http://www.sciencedirect.com/science/article/pii/S0022227520404821
work_keys_str_mv AT philipeaton effectsofmediumfattyacidconcentrationepinephrineandglucoseonpalmitatelc14oxidationandincorporationintoneutrallipidsbyskeletalmuscleinvitro
AT danielsteinberg effectsofmediumfattyacidconcentrationepinephrineandglucoseonpalmitatelc14oxidationandincorporationintoneutrallipidsbyskeletalmuscleinvitro