Effects of carbachol on extracellular Na-dependent AIB uptake in rat parotid gland

In rat parotid glands the uptake of 2-[1-14C]aminoisobutyric acid (AIB), in vitro, depends on a Na concentration gradient between the intra- and extracellular medium. Ouabain (1 mM) which inhibits the Na+-K+-ATPase and a Na+ ionophore, monensin (which dissipates the Na+ gradient), both suppress this amino acid uptake. Carbachol (5 microM) (through muscarinic receptors) evokes a decrease in AIB uptake, and in the presence of 0.1 mM ouabain the cholinergic effect is enhanced. Ouabain alone (0.1 mM) very slightly depresses the [14C]AIB uptake. Neither 1 microM isoproterenol, nor 1 microM Ca2+ ionophore A23187, which affect the membrane potential in rat parotid acinar cells, modifies the AIB uptake. When the Ca is removed from the incubation medium, carbachol still evokes a small decreasing effect on AIB uptake. From these data we can suggest that the reduced AIB uptake (induced by the cholinergic agonist) appears to be related to a process dependent on variation of intracellular Na concentration that may be triggered by the cholinergic agonist.

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The mechanisms of amino acid uptake byBrugia pahangi in vitro

Zeitschrift für Parasitenkunde Parasitology Research ◽

10.1007/bf00926960 ◽

1983 ◽

Vol 69 (2) ◽

pp. 247-253 ◽

Cited By ~ 14

Author(s):

R. E. Howells ◽

A. M. Mendis ◽

P. G. Bray

Keyword(s):

Amino Acid ◽

Amino Acid Uptake ◽

Acid Uptake

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In vitro suppression of insulin-mediated amino acid uptake in uremic skeletal muscle

American Journal of Clinical Nutrition ◽

10.1093/ajcn/33.7.1428 ◽

1980 ◽

Vol 33 (7) ◽

pp. 1428-1432 ◽

Cited By ~ 5

Author(s):

W C Arnold ◽

M A Holliday

Keyword(s):

Skeletal Muscle ◽

Amino Acid ◽

Amino Acid Uptake ◽

Acid Uptake

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Studies in Amino-acid Uptake by RD3 Sarcoma Cell Suspensions In Vitro

British Journal of Cancer ◽

10.1038/bjc.1955.50 ◽

1955 ◽

Vol 9 (3) ◽

pp. 480-485 ◽

Cited By ~ 18

Author(s):

G Wiseman ◽

F N Ghadially

Keyword(s):

Amino Acid ◽

Amino Acid Uptake ◽

Cell Suspensions ◽

Acid Uptake ◽

Sarcoma Cell

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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

British Journal Of Nutrition ◽

10.1079/bjn19760003 ◽

1976 ◽

Vol 35 (1) ◽

pp. 1-10 ◽

Cited By ~ 1

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.

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

10.26434/chemrxiv.7564991.v1 ◽

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 Trypanosoma and Leishmania genera. In Trypanosoma cruzi, 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 T. cruzi. 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 in vitro screening against T. cruzi 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 T. cruzi, 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.

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

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o58-019 ◽

1958 ◽

Vol 36 (1) ◽

pp. 171-184 ◽

Cited By ~ 9

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.

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