Blood Ammonia Elevation and Toxicity From Intravenous L-Amino Acid Administration to Dogs: the Protective Role of L-Arginine

1958 ◽  
Vol 192 (2) ◽  
pp. 311-317 ◽  
Author(s):  
John L. Fahey ◽  
Robert S. Perry ◽  
Patricia F. McCoy
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Mixture ◽  
Protective Role ◽  
Ammonium Salts ◽  
Acid Mixture ◽  
Blood Ammonia ◽  
Urea Production ◽  
Acid Administration

A nontoxic intravenous l-amino acid mixture became markedly toxic when l-arginine and l-histidine were deleted from the mixture and was capable of producing convulsions and death in dogs. Associated with these infusions was a marked increase in blood ammonia levels that coincided with the signs of toxicity. Similar toxicity was produced by infusion of ammonium salts. Administration of l-arginine·HCl prior to or with the infused amino acid mixture prevented the toxicity and the blood ammonia rise. Subsequent injection of l-arginine·HCl produced a prompt fall in blood ammonia to normal levels. l-Ornithine·HCl or l-citrulline·HCl were similarly effective. d-Arginine·HCl and l-histidine·HCl were ineffectual. Urea production was more rapid when l-arginine was added to the infused amino acid mixture. The results suggest that the Krebs-Henseleit cycle is a functioning metabolic pathway that normally is a major deterrent to the accumulation of excessive blood ammonia when large amounts of amino acids are infused.

Metabolism of dipeptides and their constituent amino acids by liver, gut, kidney, and muscle

1988 ◽  
Vol 254 (5) ◽  
pp. E588-E594 ◽  
Author(s):  
H. Lochs ◽  
P. E. Williams ◽  
E. L. Morse ◽  
N. N. Abumrad ◽  
S. A. Adibi
Keyword(s):  
Molecular Structure ◽  
Amino Acids ◽  
Steady State ◽  
Amino Acid ◽  
Infusion Rate ◽  
Amino Acid Mixture ◽  
Acid Mixture ◽  
Arterial Concentration ◽  
Balance Technique

Oligopeptides may enter the bloodstream from endogenous and exogenous sources. Using an organ-balance technique in conscious dogs, we investigated the role of individual organs in removal of two model oligopeptides (glycylleucine and glycylglycine) from plasma under steady-state conditions. Despite an identical infusion rate, arterial concentration of glycylglycine was twofold greater than that of glycylleucine. This appeared to be a result of greater fractional extraction of glycylleucine than glycylglycine by organs. Although all of the organs examined participated in removal of dipeptides from plasma, their roles varied. Liver, kidney, muscle, and gut accounted for the disappearance of 25, 24, 12, and 10% of the infused amount of glycylleucine, respectively. With glycylglycine as the substrate, disappearance across kidney accounted for 37% of the infused amount, whereas muscle, liver, and gut accounted for 18, 15, and 11%, respectively. Finally, we investigated glycine and leucine balances across organs with infusion of these amino acids in free and dipeptide forms. Glycine and leucine balances were uniquely more positive across muscle during the infusion of glycylleucine than the corresponding amino acid mixture. The possible mechanisms included release of products of glycylleucine hydrolysis by all organs except muscle. We conclude that molecular structure influences the organ extraction of dipeptides; if extraction, particularly by the liver, is not sufficiently rapid, kidney assumes a greater role than other organs in dipeptide removal from plasma.

THE ROLE OF NUTRITIONAL FACTORS IN FOOD SELECTION AND PREFERENCE AS RELATED TO LARVAL NUTRITION OF AN INSECT, PSEUDOSARCOPHAGA AFFINIS (DIPTERA, SARCOPHAGIDAE), ON SYNTHETIC DIETS

1967 ◽  
Vol 99 (12) ◽  
pp. 1310-1321 ◽  
Author(s):  
H. L. House
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Food Selection ◽  
Amino Acid Mixture ◽  
Acid Mixture ◽  
Varietal Resistance ◽  
Nutritional Factors ◽  
Glucose Levels ◽  
Nonessential Amino Acids

AbstractLarvae of Pseudosarcophaga affinis auct. nec Fallén readily discriminated between synthetic diets satisfactory for growth and those that had nutritionally important faults. The faults were lack of an essential amino acid, unsatisfactory ratios of essential and nonessential amino acids, and unsatisfactory proportions of the best amino acid mixture relative to glucose levels. Some of these were made to resemble the proportions of amino acids and glucose found by other workers in tissues of aphid-resistant and -susceptible varieties of peas. All the experiments showed that the diets chosen by larvae were those on which they grew and developed best. That larvae can relate the chemical composition of the selected foodstuff with their nutritional requirements may cast some light on varietal resistance of plants or other foodstuff to insects.

scholarly journals Effect of co-ingestion of amino acids with rice on glycaemic and insulinaemic response

2015 ◽  
Vol 114 (11) ◽  
pp. 1845-1851 ◽  
Author(s):  
Yean Yean Soong ◽  
Joseph Lim ◽  
Lijuan Sun ◽  
Christiani Jeyakumar Henry
Keyword(s):  
Amino Acids ◽  
Blood Glucose ◽  
Amino Acid ◽  
Glycaemic Index ◽  
Amino Acid Mixture ◽  
Postprandial Blood Glucose ◽  
Acid Mixture ◽  
White Rice ◽  
Amino Acid Mixtures

AbstractConsumption of high glycaemic index (GI) and glycaemic response (GR) food such as white rice has been implicated in the development of type 2 diabetes. Previous studies have reported the ability of individual amino acids to reduce GR of carbohydrate-rich foods. Because of the bitter flavour of amino acids, they have rarely been used to reduce GR. We now report the use of a palatable, preformed amino acid mixture in the form of essence of chicken. In all, sixteen healthy male Chinese were served 68 or 136 ml amino acid mixture together with rice, or 15 or 30 min before consumption of white rice. Postprandial blood glucose and plasma insulin concentrations were measured at fasting and every 15 min after consumption of the meal until 60 min after the consumption of the white rice. Subsequent blood samples were taken at 30-min intervals until 210 min. The co-ingestion of 68 ml of amino acid mixture with white rice produced the best results in reducing the peak blood glucose and GR of white rice without increasing the insulinaemic response. It is postulated that amino acid mixtures prime β-cell insulin secretion and peripheral tissue uptake of glucose. The use of ready-to-drink amino acid mixtures may be a useful strategy for lowering the high-GI rice diets consumed in Asia.

Liver extract and its free amino acids equally stimulate gastric acid secretion

1980 ◽  
Vol 239 (6) ◽  
pp. G493-G496 ◽  
Author(s):  
E. J. Feldman ◽  
M. I. Grossman
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Acid Secretion ◽  
Gastric Acid Secretion ◽  
Free Amino Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Liver Extract ◽  
Amino Acid Mixture ◽  
Acid Mixture

Using intragastric titration in dogs with gastric fistulas, dose-response studies were carried out with liver extract and with a mixture of amino acids that matched the free amino acids found in liver extract. All solutions were adjusted to pH 7.0 and osmolality to 290 mosmol x kg-1. Doses are expressed as the sum of the concentrations of all free amino acids. At each dose studied (free amino acid concentration: 2.8, 5.6, 11, 23, and 45 mM), acid secretion in response to the free amino acid mixture was not significantly different from that of liver extract. The peak response to both liver extract and the free amino acid mixture occurred with the 23-mM dose and represented about 60% of the maximal response to histamine. The serum concentrations of gastrin after liver extract and the amino acid mixture were not significantly different. It is concluded that in dogs with gastric fistula, gastric acid secretion and release of gastrin were not significantly different in response to liver extract and to a mixture of amino acids that simulated the free amino acid content of liver extract.

An abundant supply of amino acids enhances the metabolic effect of exercise on muscle protein

1997 ◽  
Vol 273 (1) ◽  
pp. E122-E129 ◽  
Author(s):  
G. Biolo ◽  
K. D. Tipton ◽  
S. Klein ◽  
R. R. Wolfe
Keyword(s):  
Amino Acids ◽  
Blood Flow ◽  
Protein Synthesis ◽  
Amino Acid ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Amino Acid Mixture ◽  
Acid Mixture ◽  
Protein Kinetics ◽  
Amino Acid Infusion

Six normal untrained men were studied during the intravenous infusion of a balanced amino acid mixture (approximately 0.15 g.kg-1.h-1 for 3 h) at rest and after a leg resistance exercise routine to test the influence of exercise on the regulation of muscle protein kinetics by hyperaminoacidemia. Leg muscle protein kinetics and transport of selected amino acids (alanine, phenylalanine, leucine, and lysine) were isotopically determined using a model based on arteriovenous blood samples and muscle biopsy. The intravenous amino acid infusion resulted in comparable increases in arterial amino acid concentrations at rest and after exercise, whereas leg blood flow was 64 +/- 5% greater after exercise than at rest. During hyperaminoacidemia, the increases in amino acid transport above basal were 30-100% greater after exercise than at rest. Increases in muscle protein synthesis were also greater after exercise than at rest (291 +/- 42% vs. 141 +/- 45%). Muscle protein breakdown was not significantly affected by hyperminoacidemia either at rest or after exercise. We conclude that the stimulatory effect of exogenous amino acids on muscle protein synthesis is enhanced by prior exercise, perhaps in part because of enhanced blood flow. Our results imply that protein intake immediately after exercise may be more anabolic than when ingested at some later time.

Amino Acids in Premature Infants

PEDIATRICS ◽  
1988 ◽  
Vol 82 (4) ◽  
pp. 680-680
Author(s):  
NIELS C. R. RÄIHÄ
Keyword(s):  
Amino Acids ◽  
Birth Weight ◽  
Amino Acid ◽  
Parenteral Nutrition ◽  
Premature Infants ◽  
Amino Acid Mixture ◽  
Acid Mixture ◽  
Metabolic Capacity ◽  
Low Birth Weight Infants ◽  
Term Infants

To the Editor.— In a recent paper in Pediatrics, Heird et al1 reported their evaluation of the use of a new amino acid mixture for parenteral nutrition in low birth weight infants. On the basis of their results the authors made the following statement: "These observations refute the concept that the metabolic capacity of LBW infants for amino acids is limited in comparison to that of term infants, older infants, and chi1dren."1(p49) Such a conclusion is not justified on the basis of the presented data.

Effects of amino acids and gastric inhibitory polypeptide on insulin release in dogs

1982 ◽  
Vol 242 (1) ◽  
pp. E53-E58
Author(s):  
J. G. Yovos ◽  
T. M. O'Dorisio ◽  
T. N. Pappas ◽  
S. Cataland ◽  
F. B. Thomas ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Insulin Release ◽  
Insulin Response ◽  
Gastric Inhibitory Polypeptide ◽  
Amino Acid Mixture ◽  
Group Iv ◽  
Acid Mixture ◽  
Group Iii ◽  
Group I

Insulin release following intravenous administration of an amino acid solution with and without a simultaneous infusion of varying amounts of porcine gastric inhibitory polypeptide (GIP) was studied in dogs. Group I received a 10-amino acid mixture (300 mosmol/kg iv) at 16.6 ml/min for 1 h; group II, amino acid mixture plus 0.5 micrograms.kg-1.h-1 porcine GIP; group III, amino acid mixture plus 1.0 micrograms.kg-1.h-1 of GIP; group IV (a and b) received either 0.5 or 1.0 micrograms.kg-1.h-1 of GIP alone. Compared to group I, groups II and III had a greater insulin response during the first 30 min of the infusion. Group] IV (a and b) showed no insulin release. Glucose concentrations showed no significant change in all groups. From these results, it is concluded that insulin release after intravenous infusion of an amino acid mixture plus GIP is greater than after amino acids or GIP alone. It appears that this effect is more pronounced in the early phase of insulin release.

Uptake and metabolism of amino acids by the dog liver perfused in situ

1962 ◽  
Vol 202 (3) ◽  
pp. 407-414 ◽  
Author(s):  
Rapier H. McMenamy ◽  
William C. Shoemaker ◽  
Jonas E. Richmond ◽  
David Elwyn
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Mixture ◽  
Acid Mixture ◽  
Sharp Rise ◽  
Dog Blood ◽  
Dog Liver ◽  
Amino Acid Concentrations ◽  
Uptake And Metabolism

Dog livers were perfused in situ for periods up to 6 hr with dog blood recycled through a pump-oxygenator. An amino acid mixture was administered for 90 min. Concentrations of amino acids were determined at intervals of 30 min or more. Rates of uptake and metabolism were calculated. After the start of perfusion, there is a fall in most plasma amino acid concentrations and a reciprocal rise in liver amino acids. Addition of amino acids causes a sharp rise in plasma amino acids. There is a rapid uptake of most of the amino acids by liver, although the concentrations of amino acids in liver fail to rise appreciably. Notable exceptions are valine, leucine, and isoleucine. Uptake of amino acids stimulates: a) an increase in the rate of synthesis of urea which ultimately accounts for 90% of the metabolized amino acids; b) a net synthesis of ornithine; and c) net noncatabolic metabolism of amino acids which may in part be protein synthesis. The results support the view that the liver temporarily stores a part of ingested amino acids as proteins, and subsequently makes them available to other organs.

Chromatographic Separation of Free Amino Acids in Table Sirups

1971 ◽  
Vol 54 (1) ◽  
pp. 61-65
Author(s):  
Arthur Russell Johnson ◽  
Richard L Corliss ◽  
Enrique Fernandez-Flores
Keyword(s):  
Amino Acids ◽  
Quantitative Analysis ◽  
Amino Acid ◽  
Ion Exchange ◽  
Free Amino Acids ◽  
Free Amino ◽  
Amino Acid Mixture ◽  
Acid Mixture ◽  
Butyl Esters ◽  
Tlc Analysis

Abstract Qualitative chromatographic methods for the separation of free amino acids in table sirups are presented to aid in the development of chemical indices of composition which may be useful in establishing the identity of sirups and detecting their adulteration. Free amino acids in 2 table sirups were isolated on ion exchange columns and eluted with dilute ammonia. The concentrated amino acid mixture in the eluate was spotted directly on silica gel G plates for TLC analysis, or the amino acids were converted to their N-trifluoroacetyl n-butyl esters for GLC analysis. As many as 16 amino acids were qualitatively separated and identified and a potential for quantitative analysis was demonstrated.

Sign in / Sign up

Export Citation Format

Share Document