QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Moore, M. C. Articles by Cherrington, A. D. Search for Related Content PubMed PubMed Citation Articles by Moore, M. C. Articles by Cherrington, A. D.

---

Article

Net Hepatic Gluconeogenic Amino Acid Uptake in Response to Peripheral versus Portal Amino Acid Infusion in Conscious Dogs¹

Mary Courtney Moore^*2, Po-Shiuan Hsieh^*, Paul J. Flakoll^,**, Doss W. Neal and Alan D. Cherrington^*,

^* Department of Molecular Physiology and Biophysics, Diabetes Research and Training Center, and ^** Department of Surgery, Vanderbilt University School of Medicine, Nashville, TN 37232

²To whom correspondence should be addressed.

These studies were conducted to determine the effect of route of gluconeogenic amino acid delivery on the hepatic uptake of the amino acids. After a sampling period with no experimental intervention (basal period), conscious dogs deprived of food for 42 h received somatostatin, intraportal infusions of insulin (3-fold basal) and glucagon (basal), and a peripheral infusion of glucose to increase the hepatic glucose load 1.5-fold basal for 240 min. A mixture of alanine, glutamate, glutamine, glycine, serine and threonine was infused intraportally at 7.6 µmol · kg^-1 · min^-1 (PorAA group, n = 6) or peripherally at 8.1 µmol · kg^-1 · min^-1 (PerAA, n = 6), to match the hepatic load of gluconeogenic amino acids in PorAA. During the infusion period, there were no differences in PerAA and PorAA, respectively, with regard to arterial plasma insulin (144 ± 18 and 162 ± 18 pmol/L), glucagon (51 ± 8 and 47 ± 11 ng/L), hepatic glucose load (199.8 ± 22.2 and 210.9 ± 16.6 µmol · kg^-1 · min^-1), net hepatic glucose uptake (2.8 ± 2.2 and 2.2 ± 1.7 µmol · kg^-1 · min^-1), hepatic load of amino acids (68 ± 14 and 62 ± 7 µmol · kg^-1 · min^-1), or net hepatic glycogen synthesis (11.1 ± 2.2 and 8.9 ± 2.2 µmol · kg^-1 · min^-1). The net hepatic uptake of glutamine (2.1 ± 0.4 vs. 0.8 ± 0.3 µmol · kg^-1 · min^-1) and the net hepatic fractional extractions of glutamine (0.11 ± 0.02 vs. 0.05 ± 0.02) and serine (0.41 ± 0.03 vs. 0.34 ± 0.02) were greater in PorAA than in PerAA (P < 0.05). We speculate that one or more of the amino acids in the mixture causes enhancement of the net hepatic uptake and fractional extraction of glutamine, and perhaps other gluconeogenic amino acids, during intraportal amino acid delivery.

KEY WORDS: • amino acids • glutamine • liver nerves • dogs

This article has been cited by other articles:

				S. Chevalier, S. C. Burgess, C. R. Malloy, R. Gougeon, E. B. Marliss, and J. A. Morais The Greater Contribution of Gluconeogenesis to Glucose Production in Obesity Is Related to Increased Whole-Body Protein Catabolism Diabetes, March 1, 2006; 55(3): 675 - 681. [Abstract] [Full Text] [PDF]

				W. Druml, G. Heinzel, and G. Kleinberger Amino acid kinetics in patients with sepsis Am. J. Clinical Nutrition, May 1, 2001; 73(5): 908 - 913. [Abstract] [Full Text] [PDF]