301
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Lew VL, Hardy MA, Ellory JC. The uncoupled extrusion of Na+ through the Na+ pump. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 323:251-66. [PMID: 4752285 DOI: 10.1016/0005-2736(73)90149-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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302
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Canessa M, Jaimovich E, de la Fuente M. Harmaline: a competitive inhibitor of Na ion in the (Na+ + K+)-ATPase system. J Membr Biol 1973; 13:263-82. [PMID: 4270922 DOI: 10.1007/bf01868232] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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303
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Ratanabanangkoon K, Hokin LE. Studies on the characterization of the sodium-potassium transport adenosinetriphosphatase. XII. Evidence for interaction of the acyl phosphate at the active site with neighboring groups. Arch Biochem Biophys 1973; 158:695-701. [PMID: 4273802 DOI: 10.1016/0003-9861(73)90563-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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304
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Post RL, Kume S. Evidence for an Aspartyl Phosphate Residue at the Active Site of Sodium and Potassium Ion Transport Adenosine Triphosphatase. J Biol Chem 1973. [DOI: 10.1016/s0021-9258(19)43350-4] [Citation(s) in RCA: 85] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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305
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306
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Hegyvary C. Effects of some organic solvents on the reactivity of sodium plus potassium ion-transport ATPase. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 311:272-91. [PMID: 4268719 DOI: 10.1016/0005-2736(73)90274-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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307
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Alonso GL, Echepare OM, Tumilasci OR. Effect of N-ethylmaleimide on (Na + + K + )-dependent adenosine triphosphatase activity at very low substrate concentration. Biochem Pharmacol 1973; 22:1239-40. [PMID: 4267638 DOI: 10.1016/0006-2952(73)90242-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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308
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Dahms AS, Boyer PD. Occurrence and Characteristics of 18O Exchange Reactions Catalyzed by Sodium- and Potassium-dependent Adenosine Triphosphatases. J Biol Chem 1973. [DOI: 10.1016/s0021-9258(19)44021-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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309
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Robinson JD. Variable affinity of the (Na+ + K+)-dependent adenosine triphosphatase for potassium. Studies using beryllium inactivation. Arch Biochem Biophys 1973; 156:232-43. [PMID: 4269801 DOI: 10.1016/0003-9861(73)90361-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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310
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de Meis L, de Mello MCF. Substrate Regulation of Membrane Phosphorylation and of Ca2+ Transport in the Sarcoplasmic Reticulum. J Biol Chem 1973. [DOI: 10.1016/s0021-9258(19)43982-3] [Citation(s) in RCA: 86] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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311
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Kaniike K, Erdmann E, Schoner W. ADP binding to (Na++K+)-activated ATPase. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 298:901-5. [PMID: 4269714 DOI: 10.1016/0005-2736(73)90394-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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312
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Blostein R, Whittington ES. Studies of High Potassium and Low Potassium Sheep Erythrocyte Membrane Sodium-Adenosine Triphosphatase. J Biol Chem 1973. [DOI: 10.1016/s0021-9258(19)44257-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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313
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Albers RW, Koval GJ. Sodium-Potassium-activated Adenosine Triphosphatase of Electrophorus Electric Organ. J Biol Chem 1973. [DOI: 10.1016/s0021-9258(19)44335-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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314
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315
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Skou JC. The relationship of the (Na + + K + )-activated enzyme system to transport of sodium and potassium across the cell membrane.. JOURNAL OF BIOENERGETICS 1973; 4:1-30. [PMID: 4269843 DOI: 10.1007/bf01516049] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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316
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Barnabei O, Luly P, Tomasi V, Trevisani A, Tria E. A study of the hormonal control in vitro of Na+-K+ activated ATPase of isolated liver plasma membrane. ADVANCES IN ENZYME REGULATION 1973; 11:273-90. [PMID: 4363201 DOI: 10.1016/0065-2571(73)90020-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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317
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Jain MK, White FP, Strickholm A, Williams E, Cordes EH. Studies concerning the possible reconstitution of an active cation pump across an artificial membrane. J Membr Biol 1972; 8:363-88. [PMID: 4263932 DOI: 10.1007/bf01868111] [Citation(s) in RCA: 49] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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318
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Bond GH. Ligand-induced conformational changes in the (Mg 2+ + Ca 2+ )-dependent ATPase of red cell membranes. BIOCHIMICA ET BIOPHYSICA ACTA 1972; 288:423-33. [PMID: 4263663 DOI: 10.1016/0005-2736(72)90263-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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319
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Activation by Adenosine Triphosphate in the Phosphorylation Kinetics of Sodium and Potassium Ion Transport Adenosine Triphosphatase. J Biol Chem 1972. [DOI: 10.1016/s0021-9258(19)44725-x] [Citation(s) in RCA: 662] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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320
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Banerjee SP, Wong SM. Effect of Potassium on Sodium-dependent Adenosine Diphosphate-Adenosine Triphosphate Exchange Activity in Kidney Microsomes. J Biol Chem 1972. [DOI: 10.1016/s0021-9258(20)81120-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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321
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Siegel GJ, Goodwin B. Sodium-Potassium-activated Adenosine Triphosphatase: Potassium Regulation of Enzyme Phosphorylation. J Biol Chem 1972. [DOI: 10.1016/s0021-9258(19)45187-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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322
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Garrahan PJ, Rega AF. Potassium activated phosphatase from human red blood cells. The effects of p-nitrophenylphosphate on carbon fluxes. J Physiol 1972; 223:595-617. [PMID: 4339052 PMCID: PMC1331464 DOI: 10.1113/jphysiol.1972.sp009864] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
1. When red cells are incubated in solutions containing p-nitrophenyl-phosphate (p-NPP), intracellular p-NPP quickly builds up reaching with a half-time of 3 min a concentration in cell water equal to one fourth the external concentration, which under the conditions used is the expected value for a divalent anion in Gibbs-Donnan equilibrium. Hence p-NPP added to the incubation media in red cells has quick access to the active centre of the membrane phosphatase which is located at the inner surface of the cell membrane.2. When p-NPP is added to the incubation media of ATP-free red cells or reconstituted ghosts, no ouabain-sensitive cation movements are detectable, suggesting that hydrolysis of p-NPP by the active transport system is unable to energize active ion translocation.3. When p-NPP concentration in the incubation media of ATP-containing cells is progressively raised, both ouabain-sensitive Na loss and ouabain-sensitive Rb uptake tend to zero along rectangular hyperbolae. For both movements inhibition is half-maximal at 77 mM external p-NPP (i.e. 19 mM internal p-NPP).4. p-NPP inhibits with equal effectiveness the Na:K and the Na:Na exchanges catalysed by the Na pump.5. The inhibitory effect of p-NPP cannot be attributed to the products of its hydrolysis, is inversely related to the intracellular ATP concentration and seems to be exerted at the inner surface of the cell membrane with an apparent affinity similar to that of the membrane phosphatase. These facts suggest that inhibition is mediated by the combination of p-NPP with the active centre of the membrane phosphatase.6. Apart from affecting the ouabain-sensitive cation movements, p-NPP increases the ouabain-resistant uptake and loss of both Na and Rb. This effect is about 4 times larger for Rb than for Na, and its kinetic analysis suggests that it is due to an increase in the passive permeability of the cell membrane.7. The increase in passive cation permeability upon addition of p-NPP cannot be attributed to the products of its hydrolysis. It seems to be due to the combination of p-NPP with a site which, like the active centre of the ouabain-resistant membrane phosphatase, faces the inner surface of the cell membrane, is unaffected by ATP and is half saturated by about 15 mM-p NPP.
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323
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Winter CG. Differential effects of digitonin on some enzyme activities of the sodium pump. BIOCHIMICA ET BIOPHYSICA ACTA 1972; 266:135-43. [PMID: 4339318 DOI: 10.1016/0005-2736(72)90129-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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324
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Robinson JD. Divalent cations as allosteric modifiers of the (Na + + K + )-dependent ATPase. BIOCHIMICA ET BIOPHYSICA ACTA 1972; 266:97-102. [PMID: 4261175 DOI: 10.1016/0005-2736(72)90124-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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325
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Siegel GJ, Josephson L. Ouabain reaction with microsomal (sodium-plus-potassium)-activated adenosinetriphosphatase. Characteristics of substrate and ion dependencies. EUROPEAN JOURNAL OF BIOCHEMISTRY 1972; 25:323-35. [PMID: 4261091 DOI: 10.1111/j.1432-1033.1972.tb01700.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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326
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Shamoo AE, Brodsky WA. Functions of the E-atp and E-P complexes in the membrane ATPase reaction. BIOCHIMICA ET BIOPHYSICA ACTA 1972; 255:220-30. [PMID: 4258774 DOI: 10.1016/0005-2736(72)90024-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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327
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Schwartz A, Lindenmayer GE, Allen JC. The Na+, K+-ATPase Membrane Transport System: Importance in Cellular Function. CURRENT TOPICS IN MEMBRANES AND TRANSPORT 1972. [DOI: 10.1016/s0070-2161(08)61057-6] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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328
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Panet R, Pick U, Selinger Z. The Role of Calcium and Magnesium in the Adenosine Triphosphatase Reaction of Sarcoplasmic Reticulum. J Biol Chem 1971. [DOI: 10.1016/s0021-9258(19)45893-6] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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329
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330
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Schoner W, Schoner W. Zum aktiven Na+, K+-Transport durch die Membran tierischer Zellen. Angew Chem Int Ed Engl 1971. [DOI: 10.1002/ange.19710832302] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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331
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Charnock JS, Cook DA, Opit LJ. Role of energized states of (Na++K+)-ATPase in the sodium pump. NATURE: NEW BIOLOGY 1971; 233:171-2. [PMID: 4256313 DOI: 10.1038/newbio233171a0] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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332
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Glynn IM, Hoffman JF. Nucleotide requirements for sodium-sodium exchange catalysed by the sodium pump in human red cells. J Physiol 1971; 218:239-56. [PMID: 4257032 PMCID: PMC1331592 DOI: 10.1113/jphysiol.1971.sp009612] [Citation(s) in RCA: 139] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
1. Resealed red cell ghosts containing a variety of nucleoside triphosphates, or a mixture of tri- and diphosphates, were allowed to lose (24)Na into a 10 mM-K medium or a K-free high-Na medium in the presence and absence of ouabain.2. Only ATP supported a ouabain-sensitive Na:K exchange in the 10 mM-K medium, or a ouabain-sensitive Na:Na exchange in the K-free medium.3. Because of ATPase and adenylate kinase activity, it is difficult to control the levels of ATP and ADP inside resealed red cell ghosts. Some control was achieved by incorporating into the ghosts an ATP regenerating system consisting of creatine phosphate and creatine kinase.4. Measurements of (24)Na efflux from ghosts prepared in this way showed that ADP is required for the ouabain-sensitive exchange of Na that occurs in K-free high-Na media, but not for the normal exchange of Na for K that occurs in K-containing media.5. The significance of these findings is discussed.
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333
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Hegyvary C, Post R. Binding of Adenosine Triphosphate to Sodium and Potassium Ion-stimulated Adenosine Triphosphatase. J Biol Chem 1971. [DOI: 10.1016/s0021-9258(18)61899-x] [Citation(s) in RCA: 296] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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334
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Skou JC, Butler KW, Hansen O. The effect of magnesium, ATP, P i , and sodium on the inhibition of the (Na + + K + )-activated enzyme system by g-strophanthin. BIOCHIMICA ET BIOPHYSICA ACTA 1971; 241:443-61. [PMID: 4258481 DOI: 10.1016/0005-2736(71)90044-7] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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335
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Schatzmann HJ, Rossi GL. (Ca 2+ + Mg 2+ )-activated membrane ATPases in human red cells and their possible relations to cation transport. BIOCHIMICA ET BIOPHYSICA ACTA 1971; 241:379-92. [PMID: 4258479 DOI: 10.1016/0005-2736(71)90037-x] [Citation(s) in RCA: 150] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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336
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Bond GH, Bader H, Post RL. Acetyl phosphate as a substitute for ATP in (Na + + K + )-dependent ATPase. BIOCHIMICA ET BIOPHYSICA ACTA 1971; 241:57-67. [PMID: 4256593 DOI: 10.1016/0005-2736(71)90303-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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337
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Askari A, Rao SN. Studies on the partial reactions catalyzed by the (Na++K+)-activated ATPase. 3. Relation of K+-dependent p-nitrophenylphosphatase to Na+ transport in red cell ghosts. BIOCHIMICA ET BIOPHYSICA ACTA 1971; 241:75-88. [PMID: 4331046 DOI: 10.1016/0005-2736(71)90305-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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338
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Banerjee SP, Khanna VK, Sen AK. Inhibition of sodium- and potassium-dependent adenosine triphosphatase by ethacrynic acid: ligand-induced modifications. Biochem Pharmacol 1971; 20:1649-60. [PMID: 4270365 DOI: 10.1016/0006-2952(71)90293-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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339
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Abstract
The effects of ouabain on potassium accumulation were studied in the dog carotid artery. It was confirmed that vascular smooth muscle lost potassium in the presence of ouabain greater than 10(-9) molar. This effect could be reversed by systematically increasing potassium in the external medium. The action of ouabain on ion accumulation was represented quantitatively with the application of a recent biophysical approach.
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340
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Comparative Properties of High Potassium and Low Potassium Sheep Erythrocyte Membrane Sodium-activated Adenosine Triphosphatase. J Biol Chem 1971. [DOI: 10.1016/s0021-9258(18)62160-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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341
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Sachs G, Long MM, Tsuji T, Hirschowitz BI. The effect of hydroxylamine on transport ATPase. BIOCHIMICA ET BIOPHYSICA ACTA 1971; 233:117-21. [PMID: 4252904 DOI: 10.1016/0005-2736(71)90363-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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342
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Koyal D, Rao SN, Askari A. Studies on the partial reactions catalyzed by the (Na+ + K+)-activated ATPase. I. Effects of simple anions and nucleoside triphosphates on the alkali-cation specificity of the p-nitrophenylphosphatase. BIOCHIMICA ET BIOPHYSICA ACTA 1971; 225:11-9. [PMID: 4250835 DOI: 10.1016/0005-2736(71)90278-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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343
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The Role of the Phosphorylated Intermediate in the Reaction of the (Na+ + K+)-Activated Enzyme System. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1971. [DOI: 10.1007/978-1-4614-4616-3_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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344
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345
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Barnett RE. Effect of monovalent cations on the ouabain iniibition of the sodium and potassium ion activated adenosine triphosphatase. Biochemistry 1970; 9:4644-8. [PMID: 4249365 DOI: 10.1021/bi00826a004] [Citation(s) in RCA: 110] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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346
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Allen JC, Lindenmayer GE, Schwartz A. An allosteric explanation for ouabain-induced time-dependent inhibition of sodium, potassium-adenosine triphosphatase. Arch Biochem Biophys 1970; 141:322-8. [PMID: 4249246 DOI: 10.1016/0003-9861(70)90138-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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347
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De Weer P. Effects of intracellular adenosine-5'-diphosphate and orthophosphate on the sensitivity of sodium efflux from squid axon to external sodium and potassium. J Gen Physiol 1970; 56:583-620. [PMID: 5475997 PMCID: PMC2225970 DOI: 10.1085/jgp.56.5.583] [Citation(s) in RCA: 93] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
A study was made of sodium efflux from squid giant axon, and its sensitivity to external K and Na. When sodium efflux from untreated axons was strongly stimulated by K(o), Na(o) was inhibitory; when dependence on K(o) was low, Na(o) had a stimulatory effect. Incipient CN poisoning or apyrase injection, which produces high intracellular levels of ADP(1) and P(i), rendered sodium efflux less dependent on external K and more dependent on external Na. Injection of ADP, AMP, arginine, or creatine + creatine phosphokinase, all of which raise ADP levels without raising P(i) levels, had the same effect as incipient CN poisoning. P(i) injection had no effect on the K sensitivity of sodium efflux. Axons depleted of arginine and phosphoarginine by injection of arginase still lost their K sensitivity when the ATP:ADP ratio was lowered and regained it partially when the ratio was raised. Rough calculations show that sodium efflux is maximally K(o)-dependent when the ATP:ADP ratio is about 10:1, becomes insensitive to K(o) when the ratio is about 1:2, and is inhibited by K(o) when the ratio is about 1:10. Deoxy-ATP mimicked ADP when injected into intact axons. Excess Mg, as well as P(i), inhibited both strophanthidin-sensitive and strophanthidin-insensitive sodium efflux. An outline is presented for a model which might explain the effects of ADP, P(i) and deoxy-ATP.
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348
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Neufeld AH, Levy HM. The Steady State Level of Phosphorylated Intermediate in Relation to the Two Sodium-dependent Adenosine Triphosphatases of Calf Brain Microsomes. J Biol Chem 1970. [DOI: 10.1016/s0021-9258(18)62801-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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349
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Lindenmayer GE, Schwartz A. Conformational changes induced in Na+, K+-ATPase by ouabain through a K+-sensitive reaction: kinetic and spectroscopic studies. Arch Biochem Biophys 1970; 140:371-8. [PMID: 4248630 DOI: 10.1016/0003-9861(70)90078-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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350
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Robinson JD. Phosphatase activity stimulated by Na+ plus K+: implications for the (Na+ plus K+)-dependent adenosine triphosphatase. Arch Biochem Biophys 1970; 139:164-71. [PMID: 4319458 DOI: 10.1016/0003-9861(70)90057-3] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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