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Glutamine metabolism in ovine splanchnic tissues: effects of infusion of ammonium bicarbonate or amino acids into the abomasum

Published online by Cambridge University Press:  09 March 2007

R. Nieto ,
T. Obitsu ,
A. Fernández-Quintela ,
D. Bremner ,
E. Milne ,
A. G. Calder  and
G. E. Lobley
R. Nieto*
Affiliation:
Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK
T. Obitsu
Affiliation:
Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK
A. Fernández-Quintela
Affiliation:
Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK
D. Bremner
Affiliation:
Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK
E. Milne
Affiliation:
Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK
A. G. Calder
Affiliation:
Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK
G. E. Lobley
Affiliation:
Rowett Research Institute, Greenburn Road, Bucksburn, Aberdeen AB21 9SB, Scotland, UK
*
*Corresponding author: Dr Rosa Nieto, present address Unidad de Nutrición Animal, Estación Experimental del Zaidín C.S.I.C., Camino del Jueves, s/n 18100, Armilla (Granada), Spain, fax +34 958 572 753, email [email protected]
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Abstract

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This study investigates the effects of increased NH3 or amino acid supply on glutamine utilisation and production by the splanchnic tissues of fed sheep. Six sheep, prepared with vascular catheters in the aorta, mesenteric, portal and hepatic veins, were fed grass pellets to 1·1×energy maintenance requirements. Each treatment involved a 4 d abomasal infusion, of either ammonium bicarbonate (AMM; 23·4 μmol/kg0·75 per min), water (CONT), or a mixture of amino acids that excluded glutamine and glutamate (AA; 46·8 μmol amino acid-N/kg0·75 per min). The treatments simulated nutritional extremes in terms of the balance of absorbed N. Kinetics across the whole gut and the liver were monitored during an intra-jugular infusion of [5-15N]glutamine. Blood flow across the whole gut or liver were unaffected by treatment. Both AMM and AA infusions doubled the hepatic release of urea-N compared with CONT (P<0·02). AA infusion decreased arterial glutamine concentration by 26 % (P<0·01) and 23 % (P<0·05) compared with AMM and CONT respectively. Despite this, whole-body glutamine flux was not affected by treatment. In contrast, AMM infusion increased hepatic glutamine production by 40 % compared with CONT (P<0·02). This provided a mechanism to ensure NH3 supply to the periphery was maintained within the normal low physiological levels. Hepatic glutamine utilisation tended to increase during AA infusion, probably to ensure equal inflows of N to the ornithine cycle. Between 6 and 10 % of NH3 absorbed across the digestive tract was derived from the amido-N of glutamine. Overall, splanchnic glutamine utilisation accounted for 45–70 % of whole-body glutamine flux.

Keywords

Glutamine15N kineticsUreagenesisAmmoniaAmino acidsPortal-drained visceraLiverSheep
Type
Research Article
Information
British Journal of Nutrition , Volume 87 , Issue 4 , April 2002 , pp. 357 - 366
Copyright
Copyright © The Nutrition Society 2002

References

Calder, AG & Smith, A (1988) Stable isotope ratio analysis of leucine and ketoisocaproic acid in blood plasma by gas chromatography/mass spectrometry. Rapid Communications in Mass Spectrometry 2, 14–16.CrossRefGoogle ScholarPubMed
Calder, PC (1994) Glutamine and the immune system – a reply. Clinical Nutrition 13, 327–328.CrossRefGoogle Scholar
Cooper, AJ, Nieves, E, Rosenpire, KC, Filc-DeRicco, S, Gelbard, AS & Brusilow, SW (1988) Short-term metabolic fate of 13N-labelled glutamate, alanine and glutamine (amide) in rat. Journal of Biological Chemistry 263, 12268–12273.CrossRefGoogle Scholar
Curthoys, NP & Watford, M (1995) Regulation of glutaminase activity and glutamine metabolism. Annual Review of Nutrition 15, 133–159.CrossRefGoogle ScholarPubMed
Darmaun, D, Matthews, DE & Bier, DM (1986) Glutamine and glutamate kinetics in humans. American Journal of Physiology 251, E117–E126.Google ScholarPubMed
Frayn, KN, Khan, K, Coppack, SW & Elia, M (1991) Amino acid metabolism in human subcutaneous adipose tissue in vivo. Clinical Science 80, 471–474.CrossRefGoogle ScholarPubMed
Garber, AJ (1980) Glutamine metabolism in skeletal muscle. In Glutamine: Metabolism, Enzymology and Regulation, pp. 259–284 [Mora, J and Palacios, R, editors]. New York, NY: Academic Press.CrossRefGoogle Scholar
Gate, JJ, Parker, DS & Lobley, GE (1999) The metabolic fate of the amido-N group of glutamine in the tissues of the gastrointestinal tract in 24-h fasted sheep. British Journal of Nutrition 81, 297–306.CrossRefGoogle Scholar
Haüssinger, D (1990) Nitrogen metabolism in liver: structural and functional organization and physiological relevance. Biochemical Journal 267, 281–290.CrossRefGoogle ScholarPubMed
Häussinger, D, Lamers, WH & Moorman, AFM (1992) Hepatocyte heterogeneity in the metabolism of amino acids and NH3. Enzyme 46, 72–73.CrossRefGoogle Scholar
Heitmann, RN & Bergman, EN (1978) Glutamine metabolism, interorgan transport, and glucogenicity in the sheep. American Journal of Physiology 234, E197–E203.Google ScholarPubMed
James, LA, Lunn, PG & Elia, M (1998) Glutamine metabolism in the gastrointestinal tract of the rat assessed by the relatives activities of glutaminase (EC 3.5.1.2.) and glutamine synthetase (EC 6.3.1.2.). British Journal of Nutrition 79, 365–372.CrossRefGoogle ScholarPubMed
Lapierre, H & Lobley, GE (2001) Nitrogen recycling in the ruminant: A Review. Journal of Dairy Science 84, Suppl E, E223–E236.CrossRefGoogle Scholar
Lobley, GE, Bremner, D, Nieto, R, Obitsu, T, Hotston Moore, A & Brown, DS (1998) Transfers of nitrogen metabolites across the ovine liver in response to short-term infusions of an amino acid mixture into the mesenteric vein. British Journal of Nutrition 80, 371–379.CrossRefGoogle ScholarPubMed
Lobley, GE, Connell, A, Lomax, MA, Brown, E, Milne, E, Calder, AG & Farningham, DAH (1995) Hepatic detoxification of ammonia in the ovine liver: possible consequences for amino acid catabolism. British Journal of Nutrition 73, 667–685.CrossRefGoogle ScholarPubMed
Lobley, GE, Connell, A, Milne, E, Newman, AM & Ewing, TA (1994) Protein synthesis in splanchnic tissues of sheep offered two levels of intake. British Journal of Nutrition 71, 3–12.CrossRefGoogle ScholarPubMed
Lobley, GE & Milano, GD (1997) Regulation of hepatic nitrogen metabolism in ruminants. Proceedings of the Nutrition Society 56, 547–563.CrossRefGoogle ScholarPubMed
Lobley, GE, Weijs, PJM, Connell, A, Calder, AG, Brown, DS & Milne, E (1996) The fate of absorbed and exogenous NH3 as influenced by forage or forage-concentrate diets in growing sheep. British Journal of Nutrition 76, 231–248.CrossRefGoogle ScholarPubMed
Luo, QL, Maltby, SA, Lobley, GE, Calder, AG & Lomax, MA (1995) The effect of amino acids on the metabolic fate of 15NH4Cl in isolated sheep hepatocytes. European Journal of Biochemistry 228, 912–917.CrossRefGoogle ScholarPubMed
Meijer, AJ, Lamers, WH & Chamuleau, RAFM (1990) Nitrogen metabolism and ornithine cycle function. Physiological Reviews 70, 701–748.CrossRefGoogle ScholarPubMed
Meijer, AJ, Lof, C, Ramos, IC & Verhoeven, AJ (1985) Control of ureagenesis. European Journal of Biochemistry 148, 189–196.CrossRefGoogle Scholar
Milano, GD (1997) Liver nitrogen transactions in sheep (Ovis aries). PhD Thesis: University of Aberdeen.Google Scholar
Milano, GD, Hotston-Moore, A & Lobley, GE (2000) Influence of hepatic ammonia removal on ureagenesis, amino acid utilisation and energy metabolism in the ovine liver. British Journal of Nutrition 83, 307–315.CrossRefGoogle ScholarPubMed
Nieto, R, Calder, AG, Anderson, SE & Lobley, GE (1996) Method for the determination of 15NH3 enrichment in biological samples by gas chromatography/electron impact ionization mass spectrometry. Journal of Mass Spectrometry 31, 289–294.3.0.CO;2-Z>CrossRefGoogle ScholarPubMed
Nissim, I, Cattano, C, Nissim, I & Yudkoff, M (1992) Relative role of the glutaminase, glutamate dehydrogenase, and AMP-deaminase pathways in hepatic ureagenesis: studies with 15N. Archives of Biochemistry and Biophysics 292, 393–401.CrossRefGoogle ScholarPubMed
Obitsu, T, Bremner, D, Milne, E & Lobley, GE (2000) Effect of abomasal glucose infusion on alanine metabolism and urea production in sheep. British Journal of Nutrition 84, 157–163.CrossRefGoogle ScholarPubMed
Orzechowski, A, Motyl, R, Pierzynowski, G & Barej, W (1987) Hepatic capacity for ammonia removal in sheep. Journal of Veterinary Medicine A 34, 108–112.CrossRefGoogle ScholarPubMed
Parker, DS, Lomax, MA, Seal, CJ & Wilton, JC (1995) Metabolic implications of ammonia production in the ruminant. Proceedings of the Nutrition Society 54, 549–563.CrossRefGoogle ScholarPubMed
Rennie, MJ, Tadros, L, Khogali, S, Ahmed, A & Taylor, PM (1994) Glutamine transport and it's metabolic effects. Journal of Nutrition 124, 1503S–1508S.CrossRefGoogle Scholar
Sarraseca, A, Milne, E, Metcalf, MJ & Lobley, GE (1998) Urea recycling in sheep: effects of intake. British Journal of Nutrition 78, 79–88.CrossRefGoogle Scholar
Souba, WW (1991) Glutamine a key substrate for the splanchnic bed. Annual Review of Nutrition 11, 285–308.CrossRefGoogle ScholarPubMed
Squires, EJ & Brosnan, JT (1983) Measurements of the turnover rate of glutamine in normal and acidotic rats. Biochemical Journal 210, 277–280.CrossRefGoogle ScholarPubMed
Symonds, H, Denise, W, Mather, L & Collins, KA (1981) The maximum hepatic capacity of the bovine liver to metabolize ammonia. Proceedings of the Nutrition Society 40, 63A.Google Scholar
Taylor, PM & Rennie, MJ (1988) Amino acid fluxes across the sinusoidal membranes of perfused rat liver: relationship with portal ammonia concentrations. In Advances in NH3 Metabolism and Hepatic Encephalopathy, pp. 45–52 [Soeters, PB, Wilson, JHP, Meijer, AJ and Holm, E, editors]. Amsterdam: Elsevier (Biomedical Division).Google Scholar
vom Dahl, S & Haüssinger, D (1996) Nutritional state and the swelling-induced inhibition of proteolysis in perfused rat liver. Journal of Nutrition 126, 395–402.CrossRefGoogle ScholarPubMed
Williams, BD & Wolfe, RR (1994) Determination of amino- and amide -15N glutamine enrichment with tertiary butyldimethylsilyl derivatives. Biological Mass Spectrometry 23, 682–688.CrossRefGoogle ScholarPubMed
Windmueller, HG & Spaeth, AE (1980) Respiratory fuels and nitrogen metabolism in vivo in small intestine of fed rats. Quantitative importance of glutamine, glutamate and aspartate. Journal of Biological Chemistry 255, 107–112.CrossRefGoogle ScholarPubMed
Wray-Cahen, D, Roberts, S, Metcalf, JA, Backwell, FRC, Bequette, BJ, Brown, DS, Sutton, JD & Lobley, GE (1997) Hepatic response to increased exogenous supply of plasma amino acids by infusion into the mesenteric vein of Holstein–Friesian cows in late gestation. British Journal of Nutrition 78, 913–930.CrossRefGoogle ScholarPubMed