Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
Electrogenic responses induced by neutral amino acids in endoderm cells from Xenopus embryo.
Bergman C, Bergman J.
???displayArticle.abstract???
1. Membrane potential measurements were carried out on endoderm cells from early Xenopus embryos in order to study neutral amino acid transport in non-excitable cells. 2. The electrical properties of the cell membrane were studied under normal conditions, then in the presence of various Na/K-pump inhibitors and at different Na, K and Cl concentrations in Ringer solution. Blockade of the Na/K-pump by ouabain, Li, cooling to 10 degrees C or low [Na]0 induces similar depolarizations of about 40 mV. 3. External application of various neutral L-amino acids induces reversible membrane depolarizations. The D-isomeric forms are found to be ineffective. The amino acid induced depolarizations are not accompanied by changes in membrane resistance. They do not show voltage dependence for potential changes of less than 40 mV. 4. The amino acid depolarization increases with increasing concentration and follows first order Michaëlian kinetics. Both the size and the time course of the amino acid depolarization depend on [Na]0. Increasing [Na]0 markedly increases the apparent affinity of the membrane receptor for amino acid. 5. Increasing [k]0 reduces the size of the amino acid response. Short exposures to either ouabain or Li do not alter the amino acid depolarization. However, p time course of the amino acid depolarization depend on [Na]0. Increasing [Na]0 markedly increases the apparent affinity of the membrane receptor for amino acid. 5. Increasing [k]0 reduces the size of the amino acid response. Short exposures to either ouabain or Li do not alter the amino acid depolarization. However, p time course of the amino acid depolarization depend on [Na]0. Increasing [Na]0 markedly increases the apparent affinity of the membrane receptor for amino acid. 5. Increasing [k]0 reduces the size of the amino acid response. Short exposures to either ouabain or Li do not alter the amino acid depolarization. However, prolonged exposure to pump inhibitors or marked alteration of the Na concentration gradient leads to a complete inhibition of amino acid responses. 6. The results are in good agreement with the notion that the amino acid induced responses reflect the activation of an electrogenic amino acid carrier, very likely co-transporting Na and amino acid.
Beck,
The sodium electrochemical potential-mediated uphill transport of D-glucose in renal brush border membrane vesicles.
1978, Pubmed
Beck,
The sodium electrochemical potential-mediated uphill transport of D-glucose in renal brush border membrane vesicles.
1978,
Pubmed Carter-Su,
Effect of membrane potential on Na+-dependent sugar transport by ATP-depleted intestinal cells.
1980,
Pubmed Christensen,
Energization of amino acid transport, studied for the Ehrlich ascites tumor cell.
1973,
Pubmed Crane,
Na+ -dependent transport in the intestine and other animal tissues.
1965,
Pubmed CRANE,
Hypothesis for mechanism of intestinal active transport of sugars.
1962,
Pubmed CSAKY,
Effect of cardioactive steroids on the active transport of non-electrolytes.
1963,
Pubmed Curran,
Kinetic relations of the Na-amino acid interaction at the mucosal border of intestine.
1967,
Pubmed Decker,
Disassembly of the zonula occludens during amphibian neurulation.
1981,
Pubmed
,
Xenbase Frizzell,
Effects of monovalent cations on the sodium-alanine interaction in rabbit ileum. Implication of anionic groups in sodium binding.
1970,
Pubmed Gupta,
Microprobe measurement of Na, K and Cl concentration profiles in epithelial cells and intercellular spaces of rabbit ileum.
1978,
Pubmed Hille,
The permeability of the sodium channel to metal cations in myelinated nerve.
1972,
Pubmed Iwatsuki,
Amino acids evoke short-latency membrane conductance increase in pancreatic acinar cells.
1980,
Pubmed Kehoe,
Electrogenic effects of neutral amino acids on neurons of Aplysia californica.
1976,
Pubmed KEYNES,
The permeability of frog muscle fibres to lithium ions.
1959,
Pubmed Kimmich,
Membrane potentials and the energetics of intestinal Na+-dependent transport systems.
1978,
Pubmed Lee,
Activities of sodium and potassium ions in epithelial cells of small intestine.
1972,
Pubmed Maruyama,
The effect of D-glucose on the electrical potential profile across the proximal tubule of newt kidney.
1972,
Pubmed Okada,
Electrical properties and active solute transport in rat small intestine. I. Potential profile changes associated with sugar and amino acid transports.
1977,
Pubmed Paterson,
Two-carrier influx of neutral amino acids into rabbit ileal mucosa.
1979,
Pubmed Preston,
Structure-affinity relationships of substrates for the neutral amino acid transport system in rabbit ileum.
1974,
Pubmed Rose,
Studies on the electrical potential profile across rabbit ileum. Effects of sugars and amino acids on transmural and transmucosal electrical potential differences.
1971,
Pubmed Schultz,
Coupled transport of sodium and organic solutes.
1970,
Pubmed Schultz,
Sodium-coupled solute transport of small intestine: a status report.
1977,
Pubmed SCHULTZ,
INTERACTIONS BETWEEN ACTIVE SODIUM TRANSPORT AND ACTIVE AMINO-ACID TRANSPORT IN ISOLATED RABBIT ILEUM.
1965,
Pubmed SCHULTZ,
ION TRANSPORT IN ISOLATED RABBIT ILEUM. I. SHORT-CIRCUIT CURRENT AND NA FLUXES.
1964,
Pubmed Ulbricht,
Ionic channels and gating currents in excitable membranes.
1977,
Pubmed Warner,
The electrical properties of the ectoderm in the amphibian embryo during induction and early development of the nervous system.
1973,
Pubmed White,
Effect of transported solutes on membrane potentials in bullfrog small intestine.
1971,
Pubmed
