Summary
The synthesis of lipid from14C-glucose and3H-alanine was measured from rat liver slices using a micro-superfusion technique that allows continuous monitoring of the perifusate output. Increase in substrate glucose results in prompt elevation of fatty acid synthesis. Insulin addition also produced an increased14C incorporation into lipid. The effects were independent. Both these factors may be active in the hypertriglyceridaemia of high carbohydrate intake or diabetes.
Résumé
La synthèse des lipides à partir du14C-glucose et de la3H-alanine fut mesurée dans des tranches de foie de rat, en utilisant une technique de microsuperfusion qui permettait l'enregistrement continu du débit du périfusat. L'addition de glucose amena une hausse immédiate de la synthèse d'acide gras. L'addition d'insuline provoqua de même une augmentation de l'incorporation de14C dans les lipides. Les effets étaient indépendants. Ces deux facteurs pourraient être actifs dans l'hypertriglycéridémie après l'absorption importante d'hydrates de carbone ou dans l'état diabétique.
Zusammenfassung
An Rattenleberschnitten wurde mit einer Mikrosuperfusionstechnik, die eine dauernde Kontrolle des Perfusatflusses erlaubt, die Lipidsynthese aus14C-G-lucose und3H-Alanin gemessen. Eine Erhöhung des Glucosesubstrats führte zu einer sofortigen Steigerung der Fettsäuresynthese. Zugegebenes Insulin erzeugte ebenfalls einen erhöhten14C-Einbau in die Lipide. Beide Effekte waren unabhängig. — Diese beiden Faktoren können in der Hypertriglycerinämie nach hoher Kohlenhydrataufnahme oder beim Diabetes wirksam sein.
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References
Ahrens, E.H., Spritz, M.: Further studies on fat and carbohydrate induced lipaemia in man. Reduction of lipaemia by feeding fat. Biochemical Problems of Lipids. Vol. 1, p. 304. New York: Frazier, A.C. Elsevier 1963.
Friedberg, S.J., Klein, R.F., Trout, D.L., Bogdanoff, M.D., Estes, E.H.: Incorporation of free fatty acids into plasma triglycerides in man. J. clin. Invest.40, 1846–1848 (1961).
Lewis, B., Mattock, M., Maervart, I. (unpublished data).
McDonald, I.: Effects of dietary carbohydrates on serum lipids in a 5-day regimen. Clin. Sci.29, 193–198 (1965).
Havel, R.J.: Conversion of plasma FFA into triglycerides of plasma lipoprotein fractions in man. Metabolism10, 1031–1036 (1961).
Tulloch, B.R., Lewis, B., Fraser, T.R.: Hypertriglyceridaemia associated with Cushing's disease and the effect of pituitary ablation (in preparation).
Letarte, J., Fraser, T.R.: Stimulation by insulin of the incorporation of U-14C-glucose into lipids released by the liver. Diabetologia5, 358–359 (1969).
Umbreit, W., Burris, R., Stauffer, J.: Manometric techniques, p. 132. Minneapolis: Burgess 1964.
Abouna, G.M.: Pig liver perfusion: the effect of preparing and flushing the liver with various balanced solutions on its subsequent viability and function. Brit. J. Surg.55, 761–768 (1968).
Junod, A., Letarte, J., Lambert, A., Stauffacher, W.: Studies in spiny mice (acomys cahirinus): metabolic state and pancreatic insulin release in vitro. Horm. Metab. Res.1, 45–52 (1969).
Dole, V.P.: A relation between NEFA in plasma and the metabolism of glucose. J. clin. Invest.35, 150–154 (1956).
Folch, J., Lees, M., Sloane Stanley, S.G.: A simple method for the isolation and purification of total lipids from animal tissue. J. biol. Chem.226, 497–509 (1957).
Eaton, R.P., Berman, M., Steinberg, D.: Kinetic studies of plasma free fatty acids and triglyceride metabolism in man. J. clin. Invest.48, 1387–1396 (1969).
Fredrickson, D.S., Levy, R.S., Lees, R.S.: Fat transport in lipoproteins: an integrated approach to mechanisms and disorders. New Engl. J. Med.276, 1970 III 32, 94, 148, 215, 273
Vester, J.W., Reino, M.L.: Hepatic glucokinase: a direct effect of insulin. Science142, 590–593 (1963).
Buschazzio, H., Exton, J.H., Park, C.: Effect of glucose on glycogen synthetase, phosphorylase and glycogen deposition in perfused rat liver. Proc. nat. Acad. Sci.65, 383–389 (1970).
Zakim, D., Perdini, R., Herman, H., Sauberlich, H.: Mechanism for differential effects of high carbohydrate diets on lipogenesis in rat liver. Biochim. biophys. Acta144, 142–149 (1967).
Galton, D.J., Wilson, J.P.D.: Glycolytic enzymes in adipose tissue of adult diabetics. Brit. med. J. 444–445 (1970).
Reaven, G., Leaver, R., Stern, M., Farquhar, R.: Role of insulin in endogenous hypertriglyceridaemia. J. clin. Invest.46, 1756–1767 (1967).
Kane, P.J., Longcope, C., Pavlatos, F., Grodsky, G.: Studies of carbohydrate metabolism in idiopathic hypertriglyceridaemia. Metabolism15, 471–486 (1965).
Havel, R.J.: Plasma lipoproteins. Adv. intern. Med.15, 117–146 (1969).
Kook, A.I., Rubenstein, D.: The role of serum lipoproteins in the release of phospholipids by rat liver slices. Biochim. biophys. Acta202, 396–398 (1970).
Nikkila, E.: Control of plasma and liver triglyceride kinetics by carbohydrate metabolism and by insulin. Adv. Lipid Res.9, 63–132 (1970).
Ruderman, N., Jones, A., Krauss, R., Shafrir, E.J.: A biochemical and morphological study of VLDL in carbohydrate induced hypertriglyceridaemia. J. clin. Invest.50, 355–367 (1971).
Wilcox, H., Dishman, G., Heinberg, M.: Hepatic lipid metabolism in experimental diabetes, IV. Incorporation of amino acid14C into lipoprotein, protein and triglyceride. J. biol. Chem.243, 666–675 (1968).
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Tulloch, B.R., Dyal, K. & Fraser, T.R. Increased lipid synthesis by liver slice in a superfusion system following raised glucose or insulin concentration. Diabetologia 8, 267–273 (1972). https://doi.org/10.1007/BF01225570
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DOI: https://doi.org/10.1007/BF01225570