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. 1985 Sep 15;230(3):675–681. doi: 10.1042/bj2300675

Decreased urea synthesis in cafeteria-diet-induced obesity in the rat.

T Barber, J R Viña, J Viña, J Cabo
PMCID: PMC1152671  PMID: 4062872

Abstract

Feeding rats with a cafeteria diet resulted in increases in total body weight and in epididymal-adipose-tissue weight. Those rats excreted significantly less N than did controls. The amount of N ingested by cafeteria-diet-fed rats was kept equal to that of controls. This decrease in N excretion is explained by a decrease in urinary excretion of urea. This may be due to the following facts. The rate of synthesis of urea from precursors by isolated hepatocytes from cafeteria-diet-fed rats was lower than in controls. In cafeteria-diet-fed rats the activities of all the enzymes of the urea cycle are decreased. The major percentage decreases are those of carbamoylphosphate synthetase (EC 6.3.4.16) and of argininosuccinate synthetase (EC 6.3.4.5), the enzymes probably involved in the regulation of the overall rate of the cycle. When rats are switched to normal chow diet, the enzyme activities return to normal values. The uptake of amino acids by liver of cafeteria-diet-fed rats is lower than in controls. These results contrast with those obtained previously by using other models of obesity in rat (i.e. genetic or hypothalamic), in which N excretion was increased.

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Selected References

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

  1. Baur H., Kasperek S., Pfaff E. Criteria of viability of isolated liver cells. Hoppe Seylers Z Physiol Chem. 1975 Jun;356(6):827–838. doi: 10.1515/bchm2.1975.356.s1.827. [DOI] [PubMed] [Google Scholar]
  2. Berry M. N., Friend D. S. High-yield preparation of isolated rat liver parenchymal cells: a biochemical and fine structural study. J Cell Biol. 1969 Dec;43(3):506–520. doi: 10.1083/jcb.43.3.506. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Calles-Escandon J., Cunningham J., Felig P. The plasma amino acid response to cafeteria feeding in the rat: influence of hyperphagia, sucrose intake, and exercise. Metabolism. 1984 Apr;33(4):364–368. doi: 10.1016/0026-0495(84)90200-2. [DOI] [PubMed] [Google Scholar]
  4. Cohen P. P. The ornithine-urea cycle: biosynthesis and regulation of carbamyl phosphate synthetase I and ornithine transcarbamylase. Curr Top Cell Regul. 1981;18:1–19. doi: 10.1016/b978-0-12-152818-8.50008-6. [DOI] [PubMed] [Google Scholar]
  5. Dunn M. A., Hartsook E. W. Comparative amino acid and protein metabolism in obese and non-obese Zucker rats. J Nutr. 1980 Sep;110(9):1865–1879. doi: 10.1093/jn/110.9.1865. [DOI] [PubMed] [Google Scholar]
  6. Frings C. S., Fendley T. W., Dunn R. T., Queen C. A. Improved determination of total serum lipids by the sulfo-phospho-vanillin reaction. Clin Chem. 1972 Jul;18(7):673–674. [PubMed] [Google Scholar]
  7. Greenway C. V., Stark R. D. Hepatic vascular bed. Physiol Rev. 1971 Jan;51(1):23–65. doi: 10.1152/physrev.1971.51.1.23. [DOI] [PubMed] [Google Scholar]
  8. Hensgens H. E., Meijer A. J. The interrelationship between ureogenesis and protein synthesis in isolated rat-liver cells. Biochim Biophys Acta. 1979 Feb 1;582(3):525–532. doi: 10.1016/0304-4165(79)90143-0. [DOI] [PubMed] [Google Scholar]
  9. Hensgens H. E., Verhoeven A. J., Meijer A. J. The relationship between intramitochondrial N-acetylglutamate and activity of carbamoyl-phosphate synthetase (ammonia). The effect of glucagon. Eur J Biochem. 1980;107(1):197–205. doi: 10.1111/j.1432-1033.1980.tb04640.x. [DOI] [PubMed] [Google Scholar]
  10. Hunninghake D., Grisolia S. A sensitive and convenient micromethod for estimation of urea, citrulline, and carbamyl derivatives. Anal Biochem. 1966 Aug;16(2):200–205. doi: 10.1016/0003-2697(66)90147-3. [DOI] [PubMed] [Google Scholar]
  11. Karakash C., Rohner-Jeanrenaud F., Hustvedt B. E., Jeanrenaud B. Nitrogen handling in adult hypothalamic obese rats. Am J Physiol. 1980 Jan;238(1):E32–E37. doi: 10.1152/ajpendo.1980.238.1.E32. [DOI] [PubMed] [Google Scholar]
  12. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  13. Lin C. P., Huang P. C. Actual nitrogen deposition in mature adult rats fed moderate to high protein diets. J Nutr. 1982 Jun;112(6):1067–1074. doi: 10.1093/jn/112.6.1067. [DOI] [PubMed] [Google Scholar]
  14. MCLEAN P., GURNEY M. W. Effect of adrenalectomy and of growth hormone on enzymes concerned with urea synthesis in rat liver. Biochem J. 1963 Apr;87:96–104. doi: 10.1042/bj0870096. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. MUNRO H. N. Carbohydrate and fat as factors in protein utilization and metabolism. Physiol Rev. 1951 Oct;31(4):449–488. doi: 10.1152/physrev.1951.31.4.449. [DOI] [PubMed] [Google Scholar]
  16. Markham R. A steam distillation apparatus suitable for micro-Kjeldahl analysis. Biochem J. 1942 Dec;36(10-12):790–791. doi: 10.1042/bj0360790. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Munro H. N. Energy and protein intakes as determinants of nitrogen balance. Kidney Int. 1978 Oct;14(4):313–316. doi: 10.1038/ki.1978.129. [DOI] [PubMed] [Google Scholar]
  18. Rolls B. J., Rowe E. A., Turner R. C. Persistent obesity in rats following a period of consumption of a mixed, high energy diet. J Physiol. 1980 Jan;298:415–427. doi: 10.1113/jphysiol.1980.sp013091. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Rothwell N. J., Stock M. J. A role for brown adipose tissue in diet-induced thermogenesis. Nature. 1979 Sep 6;281(5726):31–35. doi: 10.1038/281031a0. [DOI] [PubMed] [Google Scholar]
  20. Rothwell N. J., Stock M. J. A role for insulin in the diet-induced thermogenesis of cafeteria-fed rats. Metabolism. 1981 Jul;30(7):673–678. doi: 10.1016/0026-0495(81)90082-2. [DOI] [PubMed] [Google Scholar]
  21. Rothwell N. J., Stock M. J., Tyzbir R. S. Energy balance and mitochondrial function in liver and brown fat of rats fed "cafeteria" diets of varying protein content. J Nutr. 1982 Sep;112(9):1663–1672. doi: 10.1093/jn/112.9.1663. [DOI] [PubMed] [Google Scholar]
  22. Rémésey C., Demigné C., Aufrère J. Inter-organ relationships between glucose, lactate and amino acids in rats fed on high-carbohydrate or high-protein diets. Biochem J. 1978 Feb 15;170(2):321–329. doi: 10.1042/bj1700321. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. SCHIMKE R. T. Adaptive characteristics of urea cycle enzymes in the rat. J Biol Chem. 1962 Feb;237:459–468. [PubMed] [Google Scholar]
  24. SCHIMKE R. T. Differential effects of fasting and protein-free diets on levels of urea cycle enzymes in rat liver. J Biol Chem. 1962 Jun;237:1921–1924. [PubMed] [Google Scholar]
  25. Sclafani A., Springer D. Dietary obesity in adult rats: similarities to hypothalamic and human obesity syndromes. Physiol Behav. 1976 Sep;17(3):461–471. doi: 10.1016/0031-9384(76)90109-8. [DOI] [PubMed] [Google Scholar]
  26. Snodgrass P. J., Lin R. C., Müller W. A., Aoki T. T. Induction of urea cycle enzymes of rat liver by glucagon. J Biol Chem. 1978 Apr 25;253(8):2748–2753. [PubMed] [Google Scholar]
  27. Snodgrass P. J., Parry D. J. The kinetics of serum ornithine carbamoyltransferase. J Lab Clin Med. 1969 Jun;73(6):940–950. [PubMed] [Google Scholar]
  28. Spydevold S. O., Greenbaum A. L., Baquer N. Z., McLean P. Adaptive responses of enzymes of carbohydrate and lipid metabolism to dietary alteration in genetically obese Zucker rats (fa/fa). Eur J Biochem. 1978 Sep 1;89(2):329–339. doi: 10.1111/j.1432-1033.1978.tb12534.x. [DOI] [PubMed] [Google Scholar]
  29. Viña J. R., Williamson D. H. Utilization of L-alanine and L-glutamine by lactating mammary gland of the rat. A role for L-alanine as a lipogenic precursor. Biochem J. 1981 Jun 15;196(3):757–762. doi: 10.1042/bj1960757. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Viña J., Puertes I. R., Estrela J. M., Viña J. R., Galbis J. L. Involvement of gamma-glutamyltransferase in amino-acid uptake by the lactating mammary gland of the rat. Biochem J. 1981 Jan 15;194(1):99–102. doi: 10.1042/bj1940099. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. 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]
  32. Williamson D. H., Lopes-Vieira O., Walker B. Concentrations of free glucogenic amino acids in livers of rats subjected to various metabolic stresses. Biochem J. 1967 Aug;104(2):497–502. doi: 10.1042/bj1040497. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Wixom R. L., Reddy M. K., Cohen P. P. A concerted response of the enzymes of urea biosynthesis during thyroxine-induced metamorphosis of Rana catesbeiana. J Biol Chem. 1972 Jun 10;247(11):3684–3692. doi: 10.2172/4649772. [DOI] [PubMed] [Google Scholar]
  34. Yatzidis H. New method for direct determination of "true" creatinine. Clin Chem. 1974 Sep;20(9):1131–1134. [PubMed] [Google Scholar]

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