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The membrane potential of Ehrlich ascites tumor cells microelectrode measurements and their critical evaluation. J Membr Biol 2013; 6:269-88. [PMID: 24177444 DOI: 10.1007/bf02116574] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/1971] [Indexed: 10/25/2022]
Abstract
Intracellular potentials were measured, using a piezoelectric electromechanical transducer to impale Ehrlich ascites tumor cells with capillary microelectrodes. In sodium Ringer's, the potential immediately after the penetration was -24±7 mV, and decayed to a stable value of about -8 mV within a few msec. The peak potentials disappeared in potassium Ringer's and reappeared immediately after resuspension in sodium. Ringer's, whereas the stable potentials were only slightly influenced by the change of medium. The peak potential is in good agreement with the Nernst potential for chloride. This is also the case when cell sodium and potassium have been changed by addition of ouabain. It is concluded that the peak potentials represent the membrane potential of the unperturbed cell, and that chloride is in electrochemical equilibrium across the cell membrane.The membrane potential of about -11 mV previously reported corresponds to the stable potential in this study, and is considered as a junction potential between damaged cells and their environment. Similar potential differences were recorded between a homogenate of cells and Ringer's.The apparent membrane resistance of Ehrlich cells was about 70 Ωcm(2). This is two orders of magnitude less than the value calculated from(36)Cl fluxes, and may, in part, represent a leak in the cell membrane.For comparison, the influence of an eventual leak on measurements in red cells and mitochondria is discussed.
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Strope ER, Findl E, Conti JC, Acuff V. Pulsed Electric Fields Amd the Transmembrane Potential. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/15368378409035975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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DOSE K, DOSE U. The Mechanism of Glycolysis Inhibition by X-rays in Ascites-tumour Cells. ACTA ACUST UNITED AC 2009; 4:85-95. [PMID: 13887456 DOI: 10.1080/09553006114550971] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Wenner CE. Progress in tumor enzymology. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 29:321-90. [PMID: 4387182 DOI: 10.1002/9780470122747.ch7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Gol'dshtein DV, Rzhaninova AA, Pogorelov AG. Electron probe microanalysis of potassium and sodium in clonogenic culture of human neural stem cells. Bull Exp Biol Med 2005; 140:301-3. [PMID: 16307042 DOI: 10.1007/s10517-005-0473-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The mean potassium and sodium concentrations and distribution of potassium in clonogenic culture of human neural stem cells (neurosphere) were estimated by means of electron probe microanalysis. High sodium concentration was typical of undifferentiated cells. Potassium was irregularly distributed in the test structure. Our results confirm published data on heterogeneous morphological structure of neurospheres.
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ELSBACH P, SCHWARTZ IL. Studies on the sodium and potassium transport in rabbit polymorphonuclear leukocytes. ACTA ACUST UNITED AC 2000; 42:883-98. [PMID: 13654739 PMCID: PMC2194942 DOI: 10.1085/jgp.42.5.883] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Rabbit polymorphonuclear leukocytes obtained from peritoneal exudates, incubated at 37°C. following exposure to 4°C., actively reaccumulate potassium while little or no net extrusion of sodium takes place. Preventing the utilization of oxidative metabolism with potassium cyanide, 2,4-dinitrophenol, or a nitrogen atmosphere does not inhibit the recovery process. Inhibitors blocking anaerobic glycolysis (sodium iodoacetate and sodium fluoride in low concentrations) completely abolish the capacity to reaccumulate potassium and cause a further dissipation of the sodium and potassium gradients. Water movements have been shown to be secondary to cation shifts. It is postulated that separate transport mechanisms exist for sodium and potassium and that the process of potassium reaccumulation relies on anaerobic glycolysis as a source of energy.
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SCHULTZ SG, WILSON NL, EPSTEIN W. Cation transport in Escherichia coli. II. Intracellular chloride concentration. ACTA ACUST UNITED AC 1998; 46:159-66. [PMID: 13909522 PMCID: PMC2195246 DOI: 10.1085/jgp.46.1.159] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The intracellular Cl concentration in E. coli has been studied as a function of the Cl concentration in the growth medium and the age of the bacterial culture. The ratio of extracellular to intracellular Cl concentration is shown to be 3.0 in the logarithmic phase and 1.13 in the stationary phase, both ratios being independent of the extracellular Cl concentration. If it may be assumed that Cl is passively distributed in this organism, these results are consistent with a transmembrane P.D. of 29 mv, interior negative, during the logarithmic phase, and 3 mv, interior negative, in the stationary phase.
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HEMPLING HG. Potassium transport in the Ehrlich mouse ascites tumor cell: evidence for autoinhibition by external potassium. ACTA ACUST UNITED AC 1998; 60:181-98. [PMID: 13953688 DOI: 10.1002/jcp.1030600302] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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KATO I, PAPPENHEIMER AM. An early effect of diphtheria toxin on the metabolism of mammalian cells growing in culture. ACTA ACUST UNITED AC 1998; 112:329-49. [PMID: 13751761 PMCID: PMC2137230 DOI: 10.1084/jem.112.2.329] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
At concentrations of 0.1 Lf (0.25 µg.)/ml., or greater, diphtheria toxin produces an immediate decrease (40 ± 5 per cent) in the steady-state level of incorporation of inorganic phosphate into ATP by cultures of normal human kidney cells growing at 37°C. in the presence of glucose. The effect is readily reversible by specific antitoxin for a period of 30 minutes or more after adding toxin. Protein synthesis in these cells continues at a normal rate for 60 minutes after adding toxin and the toxin-treated cells are able to take up and concentrate potassium ions normally for at least 1 hour. Even high concentrations of toxin (5 Lf/ml. or more) fail to effect either protein synthesis or ATP formation by cultures of spleen cells from the mouse, an animal that is relatively resistant to the lethal action of the toxin. Of various inhibitors studied, antimycin A most closely resembles toxin in its action, both on protein synthesis and on ATP formation. Mouse cells are considerably more resistant to antimycin A than are human kidney cells. Human kidney cells treated with saturating doses of toxin continue to form RNA at a normal rate for about 1 hour, after which the rates of both Pi32 incorporation and of 6-C14-orotic acid incorporation into RNA sharply decline and continue at about 40 to 50 per cent their initial rate. At 37°C., S35-methionine incorporation into cell protein ceases altogether 60 to 75 minutes after addition of a saturating dose of toxin. The effect of saturating doses of toxin on S35-methionine incorporation into human kidney cell protein at different temperatures, has been studied. It is concluded from the present studies that diphtheria toxin exerts a primary, reversible effect at the surface of susceptible cells where it inhibits cytochrome-linked phosphorylation concerned with transport of inorganic phosphate across the cell membrane.
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JOSEPH NR, ENGEL MB, CATCHPOLE HR. Distribution of sodium and potassium in certain cells and tissues. Nature 1998; 191:1175-8. [PMID: 13790754 DOI: 10.1038/1911175a0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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12
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SCHULTZ SG, SOLOMON AK. Cation transport in Escherichia coli. I. Intracellular Na and K concentrations and net cation movement. ACTA ACUST UNITED AC 1998; 45:355-69. [PMID: 13909521 PMCID: PMC2195163 DOI: 10.1085/jgp.45.2.355] [Citation(s) in RCA: 194] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Methods have been developed to study the intracellular Na and K concentrations in E. coli, strain K-12. These intracellular cation concentrations have been shown to be functions of the extracellular cation concentrations and the age of the bacterial culture. During the early logarithmic phase of growth, the intracellular K concentration greatly exceeds that of the external medium, whereas the intracellular Na concentration is lower than that of the growth medium. As the age of the culture increases, the intracellular K concentration falls and the intracellular Na concentration rises, changes which are related to the fall in the pH of the medium and to the accumulation of the products of bacterial metabolism. When stationary phase cells, which are rich in Na and poor in K, are resuspended in fresh growth medium, there is a rapid reaccumulation of K and extrusion of Na. These processes represent oppositely directed net ion movements against concentration gradients, and have been shown to be dependent upon the presence of an intact metabolic energy supply.
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WALLACH DF, ULLREY D. STUDIES ON THE SURFACE AND CYTOPLASMIC MEMBRANES OF EHRLICH ASCITES CARCINOMA CELLS. II. ALKALI-CATION-ACTIVATED ADENOSINE TRIPHOSPHATE HYDROLYSIS IN A MICROSOMAL MEMBRANE FRACTION. ACTA ACUST UNITED AC 1996; 88:620-9. [PMID: 14249104 DOI: 10.1016/0926-6577(64)90104-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Smith TC, Robinson SC. Validation of the use of the lipophilic thiocyanate anion for the determination of membrane potential in Ehrlich ascites tumor cells. J Membr Biol 1989; 107:169-78. [PMID: 2716043 DOI: 10.1007/bf01871722] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The utility of the lipophilic anion thiocyanate (SCN-) as a probe for the indirect estimation of the cell membrane potential (Vm) in Ehrlich ascites tumor cells has been evaluated by comparison to direct electrophysiological measurements. SCN accumulation is consistent with first-order uptake into a single, kinetically-identifiable cellular compartment, achieving steady-state distribution in 20-30 min at 22 degrees C. The steady state distribution ratio ([SCN-]e/[SCN-]e) in physiological saline is 0.44 +/- 0.02. Treatment of the cells with propranolol (0.13 mM), an activator of Ca2+ dependent K+ channels, reduces the steady-state distribution ratio to 0.19 +/- 0.02. Conversely, treatment with BaCl2 (10 mM), an antagonist of the pathway, increases the SCN- distribution ratio to 0.62 +/- 0.01. The equilibrium potentials (VSCN) calculated under these conditions are virtually identical to direct electrophysiological measurements of the Vm made under the same conditions. The effect of varying extracellular [K+] ([K+]e) in the presence of constant [Na+]e = 100 mM has also been tested. In control cells, elevation of [K+]e from 6 to 60 mM reduces VSCN from -20.6 +/- 1.0 to -13.2 +/- 1.2 mV. Again, microelectrode measurements give excellent quantitative agreement. Propranolol increases the sensitivity of the cells to varying [K+]e, so that a 10-fold elevation reduces VSCN by approximately 31 mV. BaCl2 greatly reduces this response: a 10-fold elevation in [K+]e yielding only a 4-mV reduction in VSCN. It is concluded that the membrane potential of Ehrlich cells can be estimated accurately from SCN- distribution measurements.
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Affiliation(s)
- T C Smith
- Department of Physiology, University of Texas Health Science Center, San Antonio 78284
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Racker E, Riegler C. On the mechanism of glycolysis stimulation by neutral detergents in 3T3 and Ehrlich ascites tumor cells. Arch Biochem Biophys 1985; 240:836-42. [PMID: 2992384 DOI: 10.1016/0003-9861(85)90093-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Glycolysis of 3T3 and Ehrlich ascites tumor cells was greatly enhanced by Nonidet P-40 or Triton X-100 at about 100 micrograms/mg cell protein. This enhanced glycolysis was partly sensitive to rutamycin and partly sensitive to ouabain, suggesting that the detergent released the control of the ATPase of the mitochondria and of the plasma membrane Na+K+-ATPase. Nonidet P-40 had no effect on glycolysis in cell-free extracts from Ehrlich ascites tumor cells to which soluble mitochondrial ATPase was added. Measuring ouabain-sensitive 22Na efflux and using ouabain-sensitive lactate production as a measure of ATP hydrolysis by the Na+K+ pump, it was shown that Nonidet P-40 greatly decreased the efficiency of the Na+K+ pump. Quercetin increased the efficiency of pumping in EAT cells both in the absence and presence of the detergent.
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Ikehara T, Yamaguchi H, Sakai T, Miyamoto H. Kinetic parameters and mechanism of active cation transport in HeLa cells as studied by Rb+ influx. BIOCHIMICA ET BIOPHYSICA ACTA 1984; 775:297-307. [PMID: 6466673 DOI: 10.1016/0005-2736(84)90184-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
On incubation of HeLa cells in chilled isotonic medium, intracellular Na+ (Nac+) increased and K+ (Kc+) decreased with time, reaching steady levels after 3 h. The steady levels varied in parallel with the extracellular cation concentrations ([Na+]e, [K+]e). The cell volumes and the protein and water contents, respectively, of cells kept for 3 h in chilled media of various [Na+]e and [K+]e were not significantly different. Ouabain-sensitive Rb+ influx took place at the initial rate for a certain period which depended on [Na+]c at the beginning of the assays. The existence of two external K+ loading sites per Na+/K+-pump was demonstrated. The affinities of the sites for Rb+ as a congener of K+ were almost the same. Na+e inhibited ouabain-sensitive Rb+ influx competitively, whereas K+ was not inhibitory. Kinetic parameters were determined: the K 1/2 for Rbe+ in the absence of Na+e was 0.16 mM and th Ki for Na+e was 36.8 mM; the K 1/2 for Na+c was 19.5 mM and the Ki for K+c seemed to be extremely large. The rate equation of the ouabain-sensitive Rb+ influx suggests that Na+ and K+ are exchanged alternately through the pump by a binary mechanism.
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Corchs JL, Serrani RE, Venera G, Palchick M. Inhibition of potassium (86Rb) influx in Ehrlich ascites cells by bilirubin and ouabain. EXPERIENTIA 1982; 38:1069-71. [PMID: 7128751 DOI: 10.1007/bf01955372] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Smith TC, Robinson SC. Variable coupling of active Na+ + K+ transport in Ehrlich ascites tumor cells: regulation by external Na+ and K+. J Cell Physiol 1981; 106:407-18. [PMID: 7194348 DOI: 10.1002/jcp.1041060310] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Cheney JC, Charlton RR, Wenner CE. Calcium-ion transport by intact Ehrlich ascites tumor cells at 0°C. Cell Calcium 1980. [DOI: 10.1016/0143-4160(80)90047-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Corchs JL, Serrani RE, Palchick M. Effects of bilirubin on potassium (86Rb+) influx and ionic content in Ehrlich ascites cells. BIOCHIMICA ET BIOPHYSICA ACTA 1979; 555:512-8. [PMID: 486465 DOI: 10.1016/0005-2736(79)90404-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Potassium influx, intracellular potassium and sodium content and cellular volume were determined in vitro in Ehrlich ascites cells in the presence of up to 0.8 mM bilirubin in the incubation medium. Bilirubin uptake into cells as a function of bilirubin concentration in the incubation medium increased linearly with a molar bilirubin/albumin ratio of 20 : 1. Potassium influx and intracellular content decreased while cellular volume increased after 180 min of incubation of cells in bilirubin at a molar bilirubin/albumin ratio of 20 : 1. At a bilirubin/albumin ratio 2 : 1, potassium influx decreased, cellular volume remained unchanged, and bilirubin uptake into cells became saturated at bilirubin concentrations greater than 0.3 mM. It is suggested that bilirubin-induced alterations in potassium gradients across cell membranes may play a role in toxic effects of bilirubin on cells.
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Smith TC, Vernon KD. Correlation of the effect of Ca+2 on Na+ and K+ permeability and membrane potential of Ehrlich ascites tumor cells. J Cell Physiol 1979; 98:359-69. [PMID: 570569 DOI: 10.1002/jcp.1040980212] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The effect of Ca+2 on the transport and intracellular distribution of Na+ and K+ in Ehrlich ascites tumor cells was investigated in an effort to establish the mechanism of Ca+2-induced hyperpolarization of the cell membrane. Inclusion of Ca+2 (2 mM) in the incubation medium leads to reduced cytoplasmic concentrations of Na+, K+ and Cl- in steady cells. In cells inhibited by ouabain, Ca+2 causes a 41% decrease in the rate of net K+ loss, but is without effect on the rate of net Na+ accumulation. Net K+ flux is reduced by 50%, while net Na+ flux is unchanged in the transport-inhibited cells. The membrane potential of cells in Ca+2-free medium (-13.9 +/- 0.8 mV) is unaffected by the addition of ouabain. However, the potential of cells in Ca+2-containing medium (-23.3 +/- 1.2 mV) declines in one hour after the addition of ouabain to values comparable to those of control cells (-15.2 +/- 0.7 mV). The results of these experiments are consistent with the postulation that Ca+2 exerts two effects on Na+ and K+ transport. First, Ca+2 reduces the membrane permeability to K+ by 25%. Second, Ca+2 alters the coupling of the Na/K active transport mechanism leading to an electrogenic hyperpolarization of the membrane.
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Laris PC, Bootman M, Pershadsingh HA, Johnstone RM. The influence of cellular amino acids and the Na+ : K+ pump on the membrane potential of the Ehrlich ascites tumor cell. BIOCHIMICA ET BIOPHYSICA ACTA 1978; 512:397-414. [PMID: 213114 DOI: 10.1016/0005-2736(78)90263-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The membrane potential of the Ehrlich ascites tumor cell was shown to be influenced by its amino acid content and the activity of the Na+ :K+ pump. The membrane potential (monitored by the fluorescent dye, 3,3'-dipropylthiodicarbocyanine iodide) varied with the size of the endogenous amino acid pool and with the concentration of accumulated 2-aminoisobutyrate. When cellular amino acid content was high, the cells were hyperpolarized; as the pool declined in size, the cells were depolarized. The hyperpolarization seen with cellular amino acid required cellular Na+ but not cellular ATP. Na+ efflux was more rapid from cells containing 2-aminoisobutyrate than from cells low in internal amino acids. These observations indicate that the hyperpolarization recorded in cells with high cellular amino acid content resulted from the electrogenic co-efflux of Na+ and amino acids. Cellular ATP levels were found to decline rapidly in the presence of the dye and hence the influence of the pump was seen only if glucose was added to the cells. When the cells contained normal Na+ (approx. 30mM), the Na+ :K+ pump was shown to have little effect on the membrane potential (the addition of ouabain had little effect on the potential). When cellular Na+ was raised to 60mM, the activity of the pump changed the membrane potential from the range -25 to -30 mV to -44 to -63 mV. This hyperpolarization required external K+ and was inhibited by ouabain.
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Smith TC, Adams R. Intracellular compartmentation of Na+, K+ and Cl- in the Ehrlich ascites tumor cell: correlation with the membrane potential. J Membr Biol 1977; 35:57-74. [PMID: 560490 DOI: 10.1007/bf01869940] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The intracellular distribution of Na+, K+, Cl- and water has been studied in the Ehrlich ascites tumor cell. Comparison of the ion and water contents of whole cells with those of cells exposed to La3+ and mechanical stress indicated that La3+ treatment results in selective damage to the cell membrane and permits evaluation of cytoplasmic and nuclear ion concentrations. The results show that Na+ is sequestered within the nucleus, while K+ and Cl- are more highly concentrated in the cell cytoplasm. Reduction of the [Na+] of the incubation medium by replacement with K+ results in reduced cytoplasmic [Na+], increased [Cl-] and no change in [K+]. Nuclear concentrations of these ions are virtually insensitive to the cation composition of the medium. Concomitant measurements of the membrane potential were made. The potential in control cells was -13.7 mV. Reduction of [Na+] in the medium caused significant depolarization. The measured potential is describable by the Cl- equilibrium potential and can be accounted for in terms of cation distributions and permeabilities. The energetic implications of the intracellular compartmentation of ions are discussed.
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Abstract
K transport has been investigated during progression of cultured Ehrlich ascites tumor cells through the cell cycle. Using a double thymidine block technique, Ehrlich cells carried in continuous culture have been synchronized, as verified by simultaneous monitoring of cell number, cell volume, 3H-thymidine incorporation and mitotic index. Unidirectional influx, efflux and cell content of K have been monitored throughout the cell cycle. The nature of the pump mediated, ouabain-sensitive K flux and the furosemide-sensitive component of K flux, presumably representing K-K exchange, have also been evaluated. In early S period the ouabain sensitive component, representing the Na-K pump, comprises 52% of the total unidirectional K influx and subsequently declines during G2 period to a minimum of 40% in mid G2. During M and early S the activity again rises. As the ouabain sensitive component becomes maximal in late S period, the furosemide sensitive component diminishes from approximately 30% of the total influx to approximately 10%. The same pattern is observed in the G2 period. As the pump component diminishes, the furosemide sensitive component increases. Furosemide sensitive K efflux has also been monitored and the pattern is equivalent to that observed in the invlux studies. No change in net K flux is observed in the presence of furosemide. This indicates that the furosemide sensitive component represents an exchange component for K. These results are consistent with the conclusion that the alterations in exchange and pump fluxes are physiological events associated with progression of the cell cycle.
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Laris PC, Pershadsingh HA, Johnstone RM. Monitoring membrane potentials in Ehrlich ascites tumor cells by means of a fluorescent dye. BIOCHIMICA ET BIOPHYSICA ACTA 1976; 436:475-88. [PMID: 1276225 DOI: 10.1016/0005-2736(76)90209-1] [Citation(s) in RCA: 99] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
1. The fluorescent intensity of the dye 3,3'-dipropylthiodicarbocyanine iodide was measured in suspensions of Ehrlich ascites tumor cells in an attempt to monitor their membrane potentials under a variety of different ionic and metabolic conditions. 2. In the presence of valinomycin, fluorescent intensity is dependent on log [K+]medium (the fluorescent intensity increased with increasing [K+]medium) where K+ replaced Na+ in the medium. Cellular K+ content also influenced fluorescent intensity in the presence of valinomycin. With lower cellular K+, fluorescent intensity in the presence of valinomycin for any given concentration was increased. 3. In the presence of gramicidin fluorescent intensity was highest in Krebs-Ringer and decreased with the substitution of choline+ for Na+. 4. The observations with ionophores are consistent with the hypothesis that the dye monitors membrane potential in these cells with an increase in fluorescence indicating membrane depolarization (internal becomes more positive). 5. The estimated membrane potentials were influenced by the way in which the cells were treated. Upon dilution of the cells from 1 in 20 to 1 in 300 the initial estimations were between -50 and -60 mV. With incubation at 1 in 300 dilution for 1 h at room temperature or a 37 degrees C, the membrane potentials ranged from -18 to -42 mV. 6. Estimations of membrane potential on the basis of chloride distribution (Cl-cell/Cl-medium) in equilibrated cells ranged from -13 to -32 mV. 7. Addition of glucose to cells equilibrated at 37 degrees C for 30 min in the presence of rotenone led to a decrease in fluorescent intensity indicating hyperpolarization. Addition of ouabain in turn led to a 70 to 100% reversal of fluorescent intensity. This hyperpolarization is therefore probably due to the electrogenic activity of the sodium pump. 8. The addition of amino acids known to require external Na+ for transport increased fluorescent intensity (depolarization) reaching a maximum at higher concentrations of amino acids. Plots of 1/deltafluorescence vs. 1/[glycine] were linear with an apparent Km of 2-3 mM. The increase in fluorescence with amino acids always required external Na+. Plots of 1/fluorescence vs. 1/[Na+]medium were also linear with an apparent Km of 29 mM. These apparent Km values compare favorably with those derived from amino acid transport studies using tracers. These data indicate that the Na+-dependent transport of amino acids in these cells is electrogenic.
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OHKI SHINPEI. Membrane Potential of Phospholipid Bilayer and Biological Membranes. ACTA ACUST UNITED AC 1976. [DOI: 10.1016/b978-0-12-571810-3.50008-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
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Smith TC, Adams R. Passive cation movements in the Ehrlich ascites tumor cell: the effects of 2,4,6-trinitrobenzene sulfonic acid. J Cell Physiol 1976; 87:53-62. [PMID: 1245558 DOI: 10.1002/jcp.1040870108] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We have investigated the effects of 2,4,6-trinitrobenzene sulfonic acid (TNBS), an amino reactive reagent, on passive cation movements in Ehrlich ascites tumor cells. Incubation of tumor cells with TNBS (3 mM) results in a two phase association of TNBS with the cells. An initial, rapid phase, presumably at the level of the membrane, is independent of temperature, while the second phase increases linearly in time and is temperature dependent. Kinetic analyses of Na+ movements indicate that TNBS: (1) inhibits Na+ movement from a slowly exchanging cellular compartment, but is without effect on a more rapidly exchanging compartment; (2) does not alter net Na+ accumulation in transport-inhibited cells; and (3) is without effect on non-exchange Na+ efflux at 0 degrees C. The actions of TNBS on K+ movements depend upon temperature and the continued presence of TNBS in the environment. At 22 degrees C two minute exposure of the cells to TNBS leads to 77% inhibition of K+ efflux. With continued exposure to TNBS, the inhibition is only 42%. Reduction of the temperature to 0 degrees C decreases K+ efflux in control cells by 82%. Two minute exposure to TNBS enhances K+ efflux by 50%, while continuous exposure increases it by 144%. These results suggest: (1) TNBS interacts with several classes of membrane sites which are involved with the regulation of passive cation movements; and (2) passive Na+ and K+ movements across the cell membrane proceed by different pathways.
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Abstract
The membrane changes which occur during cellular maturation of erythroid cells have been investigated. The transport of alpha-aminoisobutyric acid, alanine, and N-methylated-alpha-aminoisobutyric acid have been studied in the erythroblastic leukemic cell, the reticulocyte, and the erythrocyte of the Long-Evans rat. The dependence of amino acid transport on extracellular sodium concentration was investigated. Erythrocytes were found to transport these amino acids only by Na-independent systems. The steady state distribution ratio was less than 1. Reticulocytes were found to transport alpha-aminoisobutyric acid and alanine by Na-dependent systems, but only small amounts of N-methylated-alpha-aminoisobutyric acid. Small amounts of these amino acids were transported by Na-independent systems. The steady state distribution ratio was greater than one for Na-dependent transport. The erythroblastic leukemia cell, a model immature erythroid cell, showed marked Na-dependence (greater than 90%) for alpha-aminoisobutyric acid and alanine transport, and greater than 80% for the Na-dependent transport of N-methyl-alpha-aminoisobutyric acid. The steady state distribution ratio for the Na-dependent transport was greater than 4. In the erythroblastic leukemic cell, at least three Na-dependent systems are present: one includes alanine and alpha-aminoisobutyric acid, but excludes N-methyl-alpha-aminoisobutyric acid; one is for alpha-aminoisobutyric acid, alanine and also N-methyl-alpha-aminoisobutyric acid; and one is for N-methyl-alpha-aminoisobutyric acid alone. In the reticulocyte, the number of Na-dependent systems are reduced to two: one for alpha-aminoisobutyric acid and alanine; one for N-methyl-alpha-aminoisobutyric acid. In the erythrocytes, no Na-dependent transport was found. Therefore, maturation of the blast cell to the mature erythrocyte is characterized by a systematic loss in the specificity and number of transport system for amino acids.
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Mills B, Tupper JT. Cation permeability and ouabain-insensitive cation flux in the Ehrlich ascites tumor cell. J Membr Biol 1975; 20:75-97. [PMID: 1121028 DOI: 10.1007/bf01870629] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The components of Na and K flux across the plasma membrane have been investigated in the Ehrlich ascites tumor cell. At intracellular K levels of approximately 100 mM, unidirectional K influx is composed of a ouabain-sensitive component, a ouabain-insensitive, nondiffusional component and a diffusional component. Unidirectional K efflux is composed of an external K-dependent component and a diffusional component. Upon reduction of intracellular K to approximately 50 mM, the external K-dependent component becomes maximal and diminishes upon further reduction of intracellular K. Unidirectional Na efflux is composed of a ouabain-sensitive component, a diffusional component and a saturable, external Na-dependent, ouabain-insensitive component. Unidirectional Na influx may be accounted for by a diffusional component, based on estimates of membrane permeability to Na, membrane potential and Na distribution. This would suggest that the ouabain-insensitive, external Na-dependent Na efflux is not Na--Na exchange. The origin of the cell membrane potential has not been previously established in the Ehrlich ascites cell. From the diffusional components of Na and K flux determined in these experiments, the membrane permeabilities to Na and K have been estimated. These permeabilities, in conjunction with the Na and K distributions across the plasma membrane, predict a cell membrane potential of - 18mV (inside negative). Passive Cl distributions in these cells predict a cell membrane potential of - 21 mV, which is in agreement with previous microelectrode measurements and dibenzyldimethylammonium distributions. The results are therefore consistent with the conclusion that the magnitude and polarity of the cell membrane potential in the Ehrlich ascites cell is dictated primarily by Na and K.
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33
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Ritter C, André J. Presence of a complete set of cytochromes despite the absence of cristae in the mitochondrial derivative of snail sperm. Exp Cell Res 1975; 92:95-101. [PMID: 165952 DOI: 10.1016/0014-4827(75)90641-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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34
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Jacquez JA. One-way fluxes of alpha-aminoisobutyric acid in Ehrlich ascites tumor cells. Trans effects and effects of sodium and potassium. J Gen Physiol 1975; 65:57-83. [PMID: 1167372 PMCID: PMC2214861 DOI: 10.1085/jgp.65.1.57] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
One-way fluxes in the steady state and one-way influxes at zero intracellular concentrations were measured for alpha-aminoisobutyric acid (AIB) in Ehrlich ascites tumor cells at 32 degrees C. The one-way fulxes show trans effects in the concentration of AIB and are dependent on sodium levels. The one-way fluxes for initial influx and for the steady state were fitted with the equations derived for the frequently used two-state carrier model. Estimates of the parameters of these equations were obtained with use of nonlinear least squares. These gave relatively good fits of the flux data and the data on steady-state distribution ratios. The two-state carrier model predicted a trans inhibition of one-way influx and a trans stimulation of one-way efflux. The former phenomenon has been demonstrated for AIB transport in Ehrlich ascites cells and there is evidence, through less firm, for the latter.
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35
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Cone CD. The role of the surface electrical transmembrane potential in normal and malignant mitogenesis. Ann N Y Acad Sci 1974; 238:420-35. [PMID: 4613241 DOI: 10.1111/j.1749-6632.1974.tb26808.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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36
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Aull F, Nachbar MS. Concanavalin A-induced alterations in sodium and potassium content of Ehrlich ascites tumor cells. J Cell Physiol 1974; 83:243-50. [PMID: 4856654 DOI: 10.1002/jcp.1040830210] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
AbstractNet fluxes of sodium and potassium were studied in Ehrlich mouse ascites tumor cells during contact with the agglutinating protein, concanavalin A. This lectin altered cation transport markedly at concentrations of 20–105 μg/ml (6–47 μg/mg cell protein). Whereas control cells extruded sodium and maintained or accumulated potassium against electrochemical gradients, in the presence of concanavalin A there was rapid net sodium entry and potassium loss. After 10–20 minutes in concanavalin A, sodium extrusion began and potassium loss diminished but these events were prevented by ouabain. The alterations in cation content induced by concanavalin A are unlikely to be the result only of agglutination since soybean agglutinin caused much smaller changes although it agglutinated the cells equally well.
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37
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Cone CD, Tongier M. Contact inhibition of division: involvement of the electrical transmembrane potential. J Cell Physiol 1973; 82:373-86. [PMID: 4590237 DOI: 10.1002/jcp.1040820307] [Citation(s) in RCA: 97] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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38
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Okada Y, Ogawa M, Aoki N, Izutsu K. The effect of K + on the membrane potential in HeLa cells. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 291:116-26. [PMID: 4684603 DOI: 10.1016/0005-2736(73)90066-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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39
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Levinson C, Smith TC, Mikiten TM. Lanthanum-induced alterations of cellular electrolytes in Ehrlich ascites tumor cells: a new view. J Cell Physiol 1972; 80:149-54. [PMID: 5071878 DOI: 10.1002/jcp.1040800116] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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40
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Mayhew E. Ion transport of ouabain resistant and sensitive Ehrlich ascites carcinoma cells. J Cell Physiol 1972; 79:441-52. [PMID: 5064753 DOI: 10.1002/jcp.1040790314] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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41
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Abstract
1. The rate of cell chloride exchange, or efflux coefficient, was measured after equilibration in media of different anionic composition.2. When sulphate substituted for chloride in the medium, the efflux coefficient was always higher than in control chloride solutions and varied inversely with external chloride concentration. In sulphate the chloride efflux coefficient varied from 19.6 to 100.7 hr(-1). The mean control efflux coefficient was 6.60 +/- 0.677 (S.E. of mean).3. In contrast, when external nitrate substituted for chloride, the efflux coefficient was independent of external chloride concentration and the same as in control chloride media. The mean value in nitrate was 6.42 +/- 0.603 (S.E. of mean). The results confirm findings of Hempling & Kromphardt (1965).4. Steady-state chloride flux varied in direct proportion to the external chloride concentration, which would be expected for passive chloride exchange. However, the slope of the line relating these variables was higher in sulphate than in nitrate and control media. Thus at any given external chloride concentration chloride flux was greater in sulphate than in nitrate and control solutions.5. It is suggested that the effect of sulphate to increase cell chloride exchange may be related to its greater tendency to bind water, relative to chloride and nitrate.
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42
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Smith TC, Mikiten TM, Levinson C. The effect of multivalent cations on the membrane potential of the Ehrlich ascites tumor cell. J Cell Physiol 1972; 79:117-25. [PMID: 5009372 DOI: 10.1002/jcp.1040790114] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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43
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Smyth H, Flahavan E, Thornes RD. The effects of protease I of Aspergillus oryzae (brinase) on membrane permeability and growth of Landschütz ascites tumour cells. Int J Cancer 1971; 7:476-82. [PMID: 5559592 DOI: 10.1002/ijc.2910070313] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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44
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Lamb JF, MacKinnon MG. The membrane potential and permeabilities of the L cell membrane to Na, K and chloride. J Physiol 1971; 213:683-9. [PMID: 5102533 PMCID: PMC1331749 DOI: 10.1113/jphysiol.1971.sp009408] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
1. The chloride content and fluxes, and the membrane potential of L cells have been measured.2. L cells contain chloride, 70 m-mole/l. intracellular water and have a flux of 5.5 p-mole/cm(2) sec.3. The membrane potential is -15 mV.K-free Krebs causes an increase in E(m) and replacing chloride with sulphate causes a temporary reduction in E(m).4. These values for E(m) and chloride, and previously obtained values for Na and K fluxes and contents were used to calculate the permeabilities of the various ions using the Goldman constant field theory. This gave permeabilities of 6.3, 4.2 and 51 x 10(-9) cm/sec for K, Na and chloride respectively, a ratio of 1:0.67:8.10.5. It is concluded that these cells have a low membrane potential because the P(K) is some 100 times lower than in skeletal muscle, therefore leading to a P(K) of the same order as P(Na).
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45
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Levinson C. Steady-state distribution of phosphate across the membrane of the Ehrlich ascites tumor cell. BIOCHIMICA ET BIOPHYSICA ACTA 1970; 203:317-25. [PMID: 5441391 DOI: 10.1016/0005-2736(70)90146-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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46
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Ryan MP, Smyth H, Hingerty D. Effects of magnesium and potassium deficiencies on composition and growth of ascites tumour cells in vivo. Life Sci 1969; 8:485-94. [PMID: 5793505 DOI: 10.1016/0024-3205(69)90246-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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47
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Mehrishi JN, Butterworth AE. Murine ascites tumour cells and lymphocytes. Effect of lysolecithin, organic mercurials and an anti-tumoral agent on the cell membrane permeability. Eur J Cancer 1969; 5:5-14. [PMID: 5780175 DOI: 10.1016/0014-2964(69)90083-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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48
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Mayhew E, Levinson C. Reversibility of ouabain induced inhibition of cell division and cation transport in Ehrlich ascites cells. J Cell Physiol 1968; 72:73-5. [PMID: 5692691 DOI: 10.1002/jcp.1040720112] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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49
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Flemming K, Mehrishi JN, Napier JA. The loss of intracellular K+ ions from the intact Ehrlich ascites carcinoma cell following irradiation with 15MeV electrons and x-rays. INTERNATIONAL JOURNAL OF RADIATION BIOLOGY AND RELATED STUDIES IN PHYSICS, CHEMISTRY, AND MEDICINE 1968; 14:175-86. [PMID: 5303351 DOI: 10.1080/09553006814550981] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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50
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Levinson C. Calcium exchange in Ehrlich mouse ascites tumor cells. BIOCHIMICA ET BIOPHYSICA ACTA 1967; 135:921-6. [PMID: 6065686 DOI: 10.1016/0005-2736(67)90061-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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