[14C]palmitate uptake in isolated rat liver mitochondria: effects of fasting, diabetes mellitus, and inhibitors of carnitine acyltransferase

J. M. Amatruda, D. H. Lockwood, Simeon Margolis, L. A. Kiesow

Research output: Contribution to journalArticle

Abstract

The rapid association of Na-[16-14C]palmitate with isolated rat liver mitochondria was measured by an oil separation method. This association was time- and temperature-dependent and was absolutely dependent on the presence of exogenous ATP and coenzyme A and partially dependent on exogenous carnitine. Carnitine dependence was enhanced at lower concentrations of [14C]palmitate. At 6.5 μM [14C]palmitate (molar ratio of palmitate to albumin equal to 0.54) the rate of association was linear for 20 sec and was increased more than 100% in the presence of carnitine. Carnitine-dependent association was inhibited by 2-bromo-palmitate, an inhibitor of carnitine acyltransferase I, but not by (+)-octanoylcarnitine, a presumed inhibitor of carnitine acyltransferase II. The association of [14C]palmitate with mitochondria was enhanced from 190 to 330% in mitochondria isolated from fasted animals and from 160 to 230% in mitochondria isolated from diabetic, ketotic animals as compared to control animals. The enhanced association with mitochondria from fasted animals was inhibited by 2-bromo-palmitate. These studies demonstrate a method of evaluating fatty acid association with mitochondria which, because of its dependence on carnitine and carnitine acyltransferase I activity, most likely represents true uptake into mitochondria. Furthermore, these studies indicate that the carnitine-dependent uptake of fatty acids into mitochondria is enhanced in the two ketotic states evaluated and that the carnitine acyltransferase system may be a regulatory site in ketone body production.

Original languageEnglish (US)
Pages (from-to)688-694
Number of pages7
JournalJournal of Lipid Research
Volume19
Issue number6
StatePublished - 1978

Fingerprint

Carnitine Acyltransferases
Mitochondria
Liver Mitochondrion
Palmitates
Medical problems
Carnitine
Liver
Rats
Fasting
Diabetes Mellitus
Animals
Carnitine O-Palmitoyltransferase
Fatty Acids
Ketone Bodies
Coenzyme A
Albumins
Oils
Adenosine Triphosphate
Temperature

ASJC Scopus subject areas

  • Endocrinology

Cite this

[14C]palmitate uptake in isolated rat liver mitochondria : effects of fasting, diabetes mellitus, and inhibitors of carnitine acyltransferase. / Amatruda, J. M.; Lockwood, D. H.; Margolis, Simeon; Kiesow, L. A.

In: Journal of Lipid Research, Vol. 19, No. 6, 1978, p. 688-694.

Research output: Contribution to journalArticle

@article{3cbb4b7c3b7b4e25a44cf3bb1eec2eef,
title = "[14C]palmitate uptake in isolated rat liver mitochondria: effects of fasting, diabetes mellitus, and inhibitors of carnitine acyltransferase",
abstract = "The rapid association of Na-[16-14C]palmitate with isolated rat liver mitochondria was measured by an oil separation method. This association was time- and temperature-dependent and was absolutely dependent on the presence of exogenous ATP and coenzyme A and partially dependent on exogenous carnitine. Carnitine dependence was enhanced at lower concentrations of [14C]palmitate. At 6.5 μM [14C]palmitate (molar ratio of palmitate to albumin equal to 0.54) the rate of association was linear for 20 sec and was increased more than 100{\%} in the presence of carnitine. Carnitine-dependent association was inhibited by 2-bromo-palmitate, an inhibitor of carnitine acyltransferase I, but not by (+)-octanoylcarnitine, a presumed inhibitor of carnitine acyltransferase II. The association of [14C]palmitate with mitochondria was enhanced from 190 to 330{\%} in mitochondria isolated from fasted animals and from 160 to 230{\%} in mitochondria isolated from diabetic, ketotic animals as compared to control animals. The enhanced association with mitochondria from fasted animals was inhibited by 2-bromo-palmitate. These studies demonstrate a method of evaluating fatty acid association with mitochondria which, because of its dependence on carnitine and carnitine acyltransferase I activity, most likely represents true uptake into mitochondria. Furthermore, these studies indicate that the carnitine-dependent uptake of fatty acids into mitochondria is enhanced in the two ketotic states evaluated and that the carnitine acyltransferase system may be a regulatory site in ketone body production.",
author = "Amatruda, {J. M.} and Lockwood, {D. H.} and Simeon Margolis and Kiesow, {L. A.}",
year = "1978",
language = "English (US)",
volume = "19",
pages = "688--694",
journal = "Journal of Lipid Research",
issn = "0022-2275",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "6",

}

TY - JOUR

T1 - [14C]palmitate uptake in isolated rat liver mitochondria

T2 - effects of fasting, diabetes mellitus, and inhibitors of carnitine acyltransferase

AU - Amatruda, J. M.

AU - Lockwood, D. H.

AU - Margolis, Simeon

AU - Kiesow, L. A.

PY - 1978

Y1 - 1978

N2 - The rapid association of Na-[16-14C]palmitate with isolated rat liver mitochondria was measured by an oil separation method. This association was time- and temperature-dependent and was absolutely dependent on the presence of exogenous ATP and coenzyme A and partially dependent on exogenous carnitine. Carnitine dependence was enhanced at lower concentrations of [14C]palmitate. At 6.5 μM [14C]palmitate (molar ratio of palmitate to albumin equal to 0.54) the rate of association was linear for 20 sec and was increased more than 100% in the presence of carnitine. Carnitine-dependent association was inhibited by 2-bromo-palmitate, an inhibitor of carnitine acyltransferase I, but not by (+)-octanoylcarnitine, a presumed inhibitor of carnitine acyltransferase II. The association of [14C]palmitate with mitochondria was enhanced from 190 to 330% in mitochondria isolated from fasted animals and from 160 to 230% in mitochondria isolated from diabetic, ketotic animals as compared to control animals. The enhanced association with mitochondria from fasted animals was inhibited by 2-bromo-palmitate. These studies demonstrate a method of evaluating fatty acid association with mitochondria which, because of its dependence on carnitine and carnitine acyltransferase I activity, most likely represents true uptake into mitochondria. Furthermore, these studies indicate that the carnitine-dependent uptake of fatty acids into mitochondria is enhanced in the two ketotic states evaluated and that the carnitine acyltransferase system may be a regulatory site in ketone body production.

AB - The rapid association of Na-[16-14C]palmitate with isolated rat liver mitochondria was measured by an oil separation method. This association was time- and temperature-dependent and was absolutely dependent on the presence of exogenous ATP and coenzyme A and partially dependent on exogenous carnitine. Carnitine dependence was enhanced at lower concentrations of [14C]palmitate. At 6.5 μM [14C]palmitate (molar ratio of palmitate to albumin equal to 0.54) the rate of association was linear for 20 sec and was increased more than 100% in the presence of carnitine. Carnitine-dependent association was inhibited by 2-bromo-palmitate, an inhibitor of carnitine acyltransferase I, but not by (+)-octanoylcarnitine, a presumed inhibitor of carnitine acyltransferase II. The association of [14C]palmitate with mitochondria was enhanced from 190 to 330% in mitochondria isolated from fasted animals and from 160 to 230% in mitochondria isolated from diabetic, ketotic animals as compared to control animals. The enhanced association with mitochondria from fasted animals was inhibited by 2-bromo-palmitate. These studies demonstrate a method of evaluating fatty acid association with mitochondria which, because of its dependence on carnitine and carnitine acyltransferase I activity, most likely represents true uptake into mitochondria. Furthermore, these studies indicate that the carnitine-dependent uptake of fatty acids into mitochondria is enhanced in the two ketotic states evaluated and that the carnitine acyltransferase system may be a regulatory site in ketone body production.

UR - http://www.scopus.com/inward/record.url?scp=0018198623&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0018198623&partnerID=8YFLogxK

M3 - Article

C2 - 99482

AN - SCOPUS:0018198623

VL - 19

SP - 688

EP - 694

JO - Journal of Lipid Research

JF - Journal of Lipid Research

SN - 0022-2275

IS - 6

ER -