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. 1970 Aug;119(1):59–65. doi: 10.1042/bj1190059

Aspects of carnitine ester metabolism in sheep liver

A M Snoswell 1, G D Henderson 1
PMCID: PMC1179318  PMID: 5485754

Abstract

1. Carnitine acetyltransferase (EC 2.3.1.7) activity in sheep liver mitochondria was 76nmol/min per mg of protein, in contrast with 1.7 for rat liver mitochondria. The activity in bovine liver mitochondria was comparable with that of sheep liver mitochondria. Carnitine palmitoyltransferase activity was the same in both sheep and rat liver mitochondria. 2. The [free carnitine]/[acetylcarnitine] ratio in sheep liver ranged from 6:1 for animals fed ad libitum on lucerne to approx. 1:1 for animals grazed on open pastures. This change in ratio appeared to reflect the ratio of propionic acid to acetic acid produced in the rumen of the sheep under the two dietary conditions. 3. In sheep starved for 7 days the [free carnitine]/[acetylcarnitine] ratio in the liver was 0.46:1. The increase in acetylcarnitine on starvation was not at the expense of free carnitine, as the amounts of free carnitine and total acid-soluble carnitine rose approximately fivefold on starvation. An even more dramatic increase in total acid-soluble carnitine of the liver was seen in an alloxan-diabetic sheep. 4. The [free CoA]/[acetyl-CoA] ratio in the liver ranged from 1:1 in the sheep fed on lucerne to 0.34:1 for animals starved for 7 days. 5. The importance of carnitine acetyltransferase in sheep liver and its role in relieving `acetyl pressure' on the CoA system is discussed.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Allred J. B., Guy D. G. Determination of coenzyme A and acetyl CoA in tissue extracts. Anal Biochem. 1969 May;29(2):293–299. doi: 10.1016/0003-2697(69)90312-1. [DOI] [PubMed] [Google Scholar]
  2. BEENAKKERS A. M., KLINGENBERG M. CARNITINE-COENZYME A TRANSACETYLASE IN MITOCHONDRIA FROM VARIOUS ORGANS. Biochim Biophys Acta. 1964 Apr 20;84:205–207. doi: 10.1016/0926-6542(64)90081-2. [DOI] [PubMed] [Google Scholar]
  3. BREMER J. Carnitine precursors in the rat. Biochim Biophys Acta. 1962 Feb 26;57:327–335. doi: 10.1016/0006-3002(62)91126-5. [DOI] [PubMed] [Google Scholar]
  4. Bohmer T., Bremer J. Propionylcarnitine. Physiological variations in vivo. Biochim Biophys Acta. 1968 May 1;152(3):559–567. doi: 10.1016/0005-2760(68)90096-9. [DOI] [PubMed] [Google Scholar]
  5. Bohmer T. Tissue levels of activated fatty acids (acylcarnitines) and the regulation of fatty acid metabo.ism. Biochim Biophys Acta. 1967 Oct 2;144(2):259–270. [PubMed] [Google Scholar]
  6. FRIEDMAN S., FRAENKEL G. Reversible enzymatic acetylation of carnitine. Arch Biochem Biophys. 1955 Dec;59(2):491–501. doi: 10.1016/0003-9861(55)90515-4. [DOI] [PubMed] [Google Scholar]
  7. FRITZ I. B., SCHULTZ S. K., SRERE P. A. Properties of partially purified carnitine acetyltransferase. J Biol Chem. 1963 Jul;238:2509–2517. [PubMed] [Google Scholar]
  8. Garland P. B., Shepherd D., Yates D. W. Steady-state concentrations of coenzyme A, acetyl-coenzyme A and long-chain fatty acyl-coenzyme A in rat-liver mitochondria oxidizing palmitate. Biochem J. 1965 Nov;97(2):587–594. doi: 10.1042/bj0970587. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Greville G. D., Tubbs P. K. The catabolism of long chain fatty acids in mammalian tissues. Essays Biochem. 1968;4:155–212. [PubMed] [Google Scholar]
  10. Hanson R. W., Ballard F. J. The relative significance of acetate and glucose as precursors for lipid synthesis in liver and adipose tissue from ruminants. Biochem J. 1967 Nov;105(2):529–536. doi: 10.1042/bj1050529. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Hirashima M., Hayakawa T., Koike M. Mammalian alpha-keto acid dehydrogenase complexes. II. An improved procedure for the preparation of 2-oxoglutarate dehydrogenase complex from pig heart muscle. J Biol Chem. 1967 Mar 10;242(5):902–907. [PubMed] [Google Scholar]
  12. Jarrett I. G., Filsell O. H. Coenzyme A in the livers of young lambs, adult sheep and rats. Biochem J. 1964 May;91(2):217–222. doi: 10.1042/bj0910217. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Katz M. L., Bergman E. N. Hepatic and portal metabolism of glucose, free fatty acids, and ketone bodies in the sheep. Am J Physiol. 1969 Apr;216(4):953–960. doi: 10.1152/ajplegacy.1969.216.4.953. [DOI] [PubMed] [Google Scholar]
  14. Koundakjian P. P., Snoswell A. M. Ketone body and fatty acid metabolism in sheep tissues. 3-Hydroxybutyrate dehydrogenase, a cytoplasmic enzyme in sheep liver and kidney. Biochem J. 1970 Aug;119(1):49–57. doi: 10.1042/bj1190049. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. LOWRY O. H., PASSONNEAU J. V., HASSELBERGER F. X., SCHULZ D. W. EFFECT OF ISCHEMIA ON KNOWN SUBSTRATES AND COFACTORS OF THE GLYCOLYTIC PATHWAY IN BRAIN. J Biol Chem. 1964 Jan;239:18–30. [PubMed] [Google Scholar]
  16. MARQUIS N. R., FRITZ I. B. ENZYMOLOGICAL DETERMINATION OF FREE CARNITINE CONCENTRATIONS IN RAT TISSUES. J Lipid Res. 1964 Apr;5:184–187. [PubMed] [Google Scholar]
  17. MAYFIELD E. D., SMITH J. L., JOHNSON B. C. METABOLISM OF ACETATE BY SHEEP LIVER HOMOGENATES. J Dairy Sci. 1965 Jan;48:93–98. doi: 10.3168/jds.s0022-0302(65)88167-x. [DOI] [PubMed] [Google Scholar]
  18. MYERS D. K., SLATER E. C. The enzymic hydrolysis of adenosine triphosphate by liver mitochondria. I. Activities at different pH values. Biochem J. 1957 Dec;67(4):558–572. doi: 10.1042/bj0670558. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Mayfield E. D., Bensadoun A., Johnson B. C. Acetate metabolism in ruminant tissues. J Nutr. 1966 Jun;89(2):189–196. doi: 10.1093/jn/89.2.189. [DOI] [PubMed] [Google Scholar]
  20. PEARSON D. J., TUBBS P. K. ACETYL-CARNITINE IN HEART AND LIVER. Nature. 1964 Apr 4;202:91–91. doi: 10.1038/202091a0. [DOI] [PubMed] [Google Scholar]
  21. PENNINGTON R. J. The metabolism of short-chain fatty acids in the sheep. I. Fatty acid utilization and ketone body production by rumen epithelium and other tissues. Biochem J. 1952 May;51(2):251–258. doi: 10.1042/bj0510251. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Pearson D. J., Tubbs P. K. Carnitine and derivatives in rat tissues. Biochem J. 1967 Dec;105(3):953–963. doi: 10.1042/bj1050953. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. SANADI D. R., LITTLEFIELD J. W., BOCK R. M. Studies on alpha-ketoglutaric oxidase. II. Purification and properties. J Biol Chem. 1952 May;197(2):851–862. [PubMed] [Google Scholar]
  24. Tubbs P. K., Garland P. B. Variations in tissue contents of coenzyme A thio esters and possible metabolic implications. Biochem J. 1964 Dec;93(3):550–557. doi: 10.1042/bj0930550. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. WIELAND O., WEISS L. Increase in liver acetyl-coenzyme A during ketosis. Biochem Biophys Res Commun. 1963 Feb 18;10:333–339. doi: 10.1016/0006-291x(63)90534-5. [DOI] [PubMed] [Google Scholar]
  26. WOLLENBERGER A., RISTAU O., SCHOFFA G. [A simple technic for extremely rapid freezing of large pieces of tissue]. Pflugers Arch Gesamte Physiol Menschen Tiere. 1960;270:399–412. [PubMed] [Google Scholar]

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