scholarly journals Amino acid uptake in the developing chick embryo heart. The effect of insulin on glycine and leucine accumulation

1968 ◽  
Vol 107 (4) ◽  
pp. 575-580 ◽  
Author(s):  
G. G. Guidotti ◽  
G. Gaja ◽  
L. Loreti ◽  
G. Ragnotti ◽  
D. A. Rottenberg ◽  
...  
Keyword(s):  
Amino Acid ◽  
Chick Embryo ◽  
Concentration Ratio ◽  
Amino Acid Uptake ◽  
Acid Uptake ◽  
Experimental Conditions ◽  
Insulin Effect ◽  
Chick Embryo Heart ◽  
Embryo Heart

1. The accumulation of [1−14C]glycine and the uptake, accumulation, incorporation (into protein, lipid, glycogen) and oxidation of l-[1−14C]leucine in 5-day-old chick embryo hearts were investigated in vitro, and the effects of insulin, puromycin and 4-methyl-2-oxopentanoic acid on these processes were studied. 2. With glycine, the ratio of concentration of the labelled amino acid in the cell water to that in medium markedly exceeded unity. Insulin significantly increased this ratio. Puromycin did not prevent the insulin effect. 3. With leucine, the concentration ratio of the labelled amino acid between intracellular and extracellular water approached unity in the absence of puromycin and was doubled by its presence. In neither case did insulin substantially alter this ratio. The addition of 4-methyl-2-oxopentanoic acid had no effect in the absence of insulin, but produced a significant increase of the concentration ratio in the presence of the hormone. 4. Leucine uptake was increased slightly by insulin in all experimental conditions except in the presence of puromycin, where a more pronounced stimulation was observed. The hormone had no effect on the incorporation of the labelled amino acid into protein, but accelerated its oxidation to carbon dioxide; the latter effect was particularly evident in the presence of puromycin and disappeared after the addition of 4-methyl-2-oxopentanoic acid.

scholarly journals Amino acid uptake in the developing chick embryo heart. The effect of insulin on α-aminoisobutyric acid accumulation

1968 ◽  
Vol 107 (4) ◽  
pp. 565-574 ◽  
Author(s):  
G. G. Guidotti ◽  
A. F. Borghetti ◽  
G. Gaja ◽  
L. Lo Reti ◽  
G. Ragnotti ◽  
...  
Keyword(s):  
Amino Acid ◽  
Chick Embryo ◽  
Incubation Medium ◽  
Transport Processes ◽  
Acid Uptake ◽  
Maximal Velocity ◽  
Aminoisobutyric Acid ◽  
Acid Accumulation ◽  
Chick Embryo Heart ◽  
Embryo Heart

1. The uptake of 14C-labelled α-aminoisobutyric acid by 5-day-old chick embryo hearts was investigated in vitro, together with the effect of insulin thereon. 2. At equilibrium the distribution ratio of this amino acid analogue between intracellular and extracellular water attained values greater than unity. Insulin enhanced the rate of α-aminoisobutyric acid accumulation and increased the value of its final concentration in the cell water. 3. The rate of α-aminoisobutyric acid accumulation and the effect of insulin on it were independent of the presence of glucose in the incubation medium. Bovine and chicken insulin were equally effective, and the action of the hormone was specifically prevented by an anti-insulin serum but not by puromycin. 4. A linear relationship was observed between the intracellular accumulation of the analogue and the logarithm of the insulin concentration in the range 50μunits–100m-units/ml. of incubation medium. 5. Evidence was obtained for the occurrence of two different transport processes for α-aminoisobutyric acid in the chick embryo heart: one subject to saturation and one that was not saturated by reasonable concentrations of the analogue. Insulin increased the effectiveness of the saturable component, increasing the maximal velocity of transport without altering the concentration for half-maximal velocity of transport, and decreased the contribution of the non-saturable component.

scholarly journals Kinetic analysis of insulin action on amino acid uptake by isolated chick embryo heart cells

1971 ◽  
Vol 122 (4) ◽  
pp. 409-414 ◽  
Author(s):  
G. G. Guidotti ◽  
A. F. Borghetti ◽  
Britta Lüneburg ◽  
G. C. Gazzola
Keyword(s):  
Carbon Dioxide ◽  
Amino Acids ◽  
Amino Acid ◽  
Chick Embryo ◽  
Transport Systems ◽  
Heart Cells ◽  
Acid Uptake ◽  
Maximal Velocity ◽  
Chick Embryo Heart ◽  
Embryo Heart

1. Isolated chick embryo heart cells were used to investigate the mode of action of insulin on the transport of three naturally occurring amino acids: l-proline, l-serine and glycine. Initial velocities of uptake were measured over a period of 5min with an 80-fold range of amino acid concentration. Corrections for amino acid diffusion, incorporation into protein and conversion into carbon dioxide were introduced. 2. The uptake processes approximated Michaelis–Menten kinetics within definite ranges of amino acid concentrations. A single transport system for proline and at least two transport systems for serine and glycine were detected. 3. The kinetic effects of insulin on transport systems for the amino acids tested were consistent with an acceleration of the maximal velocity of the process, without substantial changes in substrate concentration for half-maximal transport velocity. 4. These hormonal effects were not essentially altered by the corrections for amino acid incorporation into protein and conversion into carbon dioxide.

The mechanisms of amino acid uptake byBrugia pahangi in vitro

1983 ◽  
Vol 69 (2) ◽  
pp. 247-253 ◽  
Author(s):  
R. E. Howells ◽  
A. M. Mendis ◽  
P. G. Bray
Keyword(s):  
Amino Acid ◽  
Amino Acid Uptake ◽  
Acid Uptake

scholarly journals Action of growth hormone in vitro on the net uptake and incorporation into protein of amino acids in muscle from intact rabbits given protein-deficient diets

1976 ◽  
Vol 35 (1) ◽  
pp. 1-10 ◽  
Author(s):  
M. R. Turner ◽  
P. J. Reeds ◽  
K. A. Munday
Keyword(s):  
Amino Acids ◽  
Growth Hormone ◽  
Protein Synthesis ◽  
Amino Acid ◽  
De Novo ◽  
Amino Acid Uptake ◽  
Acid Uptake ◽  
Amino Acid Incorporation ◽  
Acid Incorporation

1. Net amino acid uptake, and incorporation into protein have been measured in vitro in the presence and absence of porcine growth hormone (GH) in muscle from intact rabbits fed for 5 d on low-protein (LP), protein-free (PF) or control diets.2. In muscle from control and LP animals GH had no effect on the net amino acid uptake but stimulated amino acid incorporation into protein, although this response was less in LP animals than in control animals.3. In muscle from PF animals, GH stimulated both amino acid incorporation into protein and the net amino acid uptake, a type of response which also occurs in hypophysectomized animals. The magnitude of the effect of GH on the incorporation of amino acids into protein was reduced in muscle from PF animals.4. The effect of GH on the net amino acid uptake in PF animals was completely blocked by cycloheximide; the uptake effect of GH in these animals was dependent therefore on de novo protein synthesis.5. It is proposed that in the adult the role of growth hormone in protein metabolism is to sustain cellular protein synthesis when there is a decrease in the level of substrate amino acids, similar to that which occurs during a short-term fast or when the dietary protein intake is inadequate.

scholarly journals Rationally Design of a Proline Transporter Inhibitor with Anti-Trypanosoma Cruzi Activity

2019 ◽  
Author(s):  
Lucia Fargnoli ◽  
Esteban A. Panozzo-Zénere ◽  
Lucas Pagura ◽  
María Julia Barisón ◽  
Julia A. Cricco ◽  
...  
Keyword(s):  
Amino Acid ◽  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Variable Region ◽  
Amino Acid Uptake ◽  
Acid Uptake ◽  
Cell Infection ◽  
Atp Production ◽  
First Case

L-Proline is an important amino acid for the pathogenic protists belonging to <i>Trypanosoma</i> and <i>Leishmania </i>genera. In <i>Trypanosoma cruzi</i>, the etiological agent of Chagas disease, this amino acid is involved in fundamental biological processes such as ATP production, differentiation of the insect and intracellular stages, the host cell infection and the resistance to a variety of stresses, including nutritional and osmotic as well as oxidative imbalance. In this study, we explore the L-Proline uptake as a chemotherapeutic target for <i>T. cruzi</i>. For this, we propose a novel rational to design inhibitors containing this amino acid as a recognizable motif. This rational consists of conjugating the amino acid (proline in this case) to a linker and a variable region able to block the transporter. We obtained a series of sixteen 1,2,3-triazolyl-proline derivatives through alkylation and copper(I)-catalyzed azide-alkyne cycloaddition (click chemistry) for <i>in vitro</i> screening against <i>T. cruzi </i>epimastigotes, trypanocidal activity and proline uptake. We successfully obtained inhibitors that are able to interfere with the amino acid uptake, which validated the first example of a rationally designed chemotherapeutic agent targeting a metabolite's transport. Additionally, we designed and prepared fluorescent analogues of the inhibitors that were successfully taken up by <i>T. cruzi</i>, allowing following up their intracellular fate. In conclusion, we successfully designed and produced a series of metabolite uptake inhibitors. This is one of few examples of rationally designed amino acid transporter inhibitor, being the first case where the strategy is applied on the development of chemotherapy against Chagas disease. This unprecedented development is remarkable having in mind that only a small percent of the metabolite transporters has been studied at the structural and/or molecular level.

THE METABOLISM OF ANIMAL TISSUES CULTIVATED IN VITRO: II. AMINO ACID METABOLISM OF CHICK EMBRYONIC KIDNEY, CHICK EMBRYONIC LIVER, AND MONKEY KIDNEY CORTEX CULTURES

1958 ◽  
Vol 36 (1) ◽  
pp. 171-184 ◽  
Author(s):  
Arthur E. Pasieka ◽  
Helen J. Morton ◽  
Joseph F. Morgan
Keyword(s):  
Tissue Culture ◽  
Amino Acid ◽  
Culture Medium ◽  
Synthetic Medium ◽  
Amino Acid Uptake ◽  
Monkey Kidney ◽  
Kidney Cortex ◽  
Acid Uptake ◽  
Embryonic Liver

Freshly-explanted chick embryonic kidney, chick embryonic liver, and trypsinized monkey kidney cortex cells have been cultivated in vitro in completely synthetic medium M 150. The amino acid changes in the nutrient medium during cultivation of these tissues have been studied by paper chromatography. A characteristic pattern of amino acid uptake and accumulation in the used culture medium has been demonstrated with each type of tissue culture. It has also been shown that, while the amino acid changes in the medium are different with each type of tissue culture, all cultures examined removed adenine from the medium and liberated small amounts of material thought to be hypoxanthine.

Amino acid uptake by neurones and glial cells from embryonic cockroach brain growing in vitro

1987 ◽  
Vol 33 (10) ◽  
pp. 761-768 ◽  
Author(s):  
Carol A. Beadle ◽  
Isabelle Bermudez ◽  
David J. Beadle
Keyword(s):  
Amino Acid ◽  
Glial Cells ◽  
Amino Acid Uptake ◽  
Acid Uptake

Hepatic Amino Acid Uptake Is Decreased in Lactating Rats. In Vivo and In Vitro Studies

1994 ◽  
Vol 124 (11) ◽  
pp. 2163-2171 ◽  
Author(s):  
José García de la Asunción ◽  
Amparo Devesa ◽  
Juan R. Viña ◽  
Teresa Barber
Keyword(s):  
Amino Acid ◽  
Amino Acid Uptake ◽  
In Vitro Studies ◽  
Acid Uptake
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