scholarly journals Lithium transport pathways in human red blood cells.

1978 ◽  
Vol 72 (2) ◽  
pp. 233-247 ◽  
Author(s):  
G N Pandey ◽  
B Sarkadi ◽  
M Haas ◽  
R B Gunn ◽  
J M Davis ◽  
...  
Keyword(s):  
External Medium ◽  
Red Cells ◽  
Red Cell Membrane ◽  
Transport Pathways ◽  
Human Red Blood Cells ◽  
Lithium Transport ◽  
Ca Ions ◽  
Dominant Cation ◽  
Human Red Cells ◽  
In Cells

In human red cells, Li is extruded against its own concentration gradient if the external medium contains Na as a dominant cation. This uphill net Li extrusion occurs in the presence of external Na but not K, Rb, Cs, choline, Mg, or Ca, is ouabain-insensitive, inhibited by phloretin, and does not require the presence of cellular ATP. Li influx into human red cells has a ouabain-sensitive and a ouabain-insensitive but phloretin-sensitive component. Ouabain-sensitive Li influx is competitively inhibited by external K and Na and probably involves the site on which the Na-K pump normally transports K into red cells. Ouabain does not inhibit Li efflux from red cells containing Li concentrations below 10 mM in the presence of high internal Na or K, whereas a ouabain-sensitive Li efflux can be measured in cells loaded to contain 140 mM Li in the presence of little or no internal Na or K. Ouabain-insensitive Li efflux is stimulated by external Na and not by K, Rb, Cs, choline, Mg, or Ca ions. Na-dependent Li efflux does not require the presence of cellular ATP and is inhibited by phloretin, furosemide, quinine, and quinidine. Experiments carried out in cells loaded in the presence of nystatin to contain either only K or only Na show that the ouabain-insensitive, phloretin-inhibited Li movements into or out of human red cells are stimulated by Na on the trans side and inhibited by Na on the cis side of the red cell membrane. The characteristics of the Na-dependent unidirectional Li fluxes and uphill Li extrusion are similar, suggesting that they are mediated by the same Na-Li countertransport system.

scholarly journals Kinetics and stoichiometry of Na-dependent Li transport in human red blood cells.

1978 ◽  
Vol 72 (2) ◽  
pp. 249-265 ◽  
Author(s):  
B Sarkadi ◽  
J K Alifimoff ◽  
R B Gunn ◽  
D C Tosteson
Keyword(s):  
Transport System ◽  
Red Cells ◽  
Normal Male ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Human Red Blood Cells ◽  
Na Efflux ◽  
Tightly Coupled ◽  
Male Subjects ◽  
Human Red Cells

This paper describes the kinetics and stoichiometry of a tightly coupled Na-Li exchange transport system in human red cells. The system is inhibited by phloretin and furosemide but not by ouabain. Li influx by this system increases and saturates with increasing concentrations of external Li and internal Na and is inhibited competitively by external Na. Comparable functions relate Li efflux and Na efflux to internal and external Li and Na concentrations. Analysis of these relations yields the following values for the ion concentrations required to half-maximally activate the transport system: internal Na and Li 9.0 and 0.5 mM, respectively, external Na and Li 25 and 1.5 mM, respectively. The system performs a 1:1 exchange of Na and Li moving in opposite directions across the red cell membrane. We found no evidence for a simultaneous transport of more than one Na and Li by the system. The maximum transport rate of Na-dependent Li transport varied between 0.1 and 0.37 mmol/(liter of cells X h) in the red cells of the five normal male subjects studied. No significant variations between individual subjects were observed for bicarbonate-stimulated Li transport and for the residual Li fluxes which occur in the absence of bicarbonate and in the presence of ouabain plus phloretin.

scholarly journals Quantitative immunoferritin microscopy of Fya, Fyb, Jka, U, and Dib antigen site numbers on human red cells

Blood ◽  
1980 ◽  
Vol 56 (6) ◽  
pp. 969-977 ◽  
Author(s):  
SP Masouredis ◽  
E Sudora ◽  
L Mahan ◽  
EJ Victoria
Keyword(s):  
Distribution Patterns ◽  
Red Cells ◽  
Diverse Group ◽  
Red Cell ◽  
Human Erythrocyte Membrane ◽  
Red Cell Membrane ◽  
Quantitative Estimates ◽  
Equilibrium Binding ◽  
Antigen Site ◽  
Human Red Cells

Abstract The Fya, Fyb, Jka, U, and Dib antigen site numbers and ultrastructural distribution patterns on the human erythrocyte membrane were determined using quantitative immunoferritin microscopy. For homozygous antigen- positive red cells, the average number of determinants per red cell was about 14,000 for Jka, 17,000 for Fya and Fyb, 19,000 for Dib, and 23,000 for the U antigen, assuming that the equilibrium binding observed represented 80% saturation of the accessible antigen sites. The site numbers for this group of antigens were less than that for the Rh antigens, but considerably more than the Kell and Cellano antigens. The technique used was capable of demonstrating a twofold difference in antigen density between heterozygous and homozygous Fy (a+) red cells. More than 85% of the Fya and Fyb antigen sites were lost following pretreatment of the red cells with papain, consistent with the serologic lability of the Fy antigens following proteolysis. The ferritin distribution observed following conjugate staining of antibody- sensitized ghost membranes was similar for all five antigens studied and showed a random, clustered ferritin pattern. Although the quantitative estimates are valid, the remarkable similarity in antigen distribution pattern for this diverse group of antigens, as well as other considerations, suggest that the findings with ghose membranes probably do not reflect faithfully the antigen arrangement on the intact red cell membrane.

scholarly journals Quantitative immunoferritin microscopy of Fya, Fyb, Jka, U, and Dib antigen site numbers on human red cells

Blood ◽  
1980 ◽  
Vol 56 (6) ◽  
pp. 969-977
Author(s):  
SP Masouredis ◽  
E Sudora ◽  
L Mahan ◽  
EJ Victoria
Keyword(s):  
Distribution Patterns ◽  
Red Cells ◽  
Diverse Group ◽  
Red Cell ◽  
Human Erythrocyte Membrane ◽  
Red Cell Membrane ◽  
Quantitative Estimates ◽  
Equilibrium Binding ◽  
Antigen Site ◽  
Human Red Cells

The Fya, Fyb, Jka, U, and Dib antigen site numbers and ultrastructural distribution patterns on the human erythrocyte membrane were determined using quantitative immunoferritin microscopy. For homozygous antigen- positive red cells, the average number of determinants per red cell was about 14,000 for Jka, 17,000 for Fya and Fyb, 19,000 for Dib, and 23,000 for the U antigen, assuming that the equilibrium binding observed represented 80% saturation of the accessible antigen sites. The site numbers for this group of antigens were less than that for the Rh antigens, but considerably more than the Kell and Cellano antigens. The technique used was capable of demonstrating a twofold difference in antigen density between heterozygous and homozygous Fy (a+) red cells. More than 85% of the Fya and Fyb antigen sites were lost following pretreatment of the red cells with papain, consistent with the serologic lability of the Fy antigens following proteolysis. The ferritin distribution observed following conjugate staining of antibody- sensitized ghost membranes was similar for all five antigens studied and showed a random, clustered ferritin pattern. Although the quantitative estimates are valid, the remarkable similarity in antigen distribution pattern for this diverse group of antigens, as well as other considerations, suggest that the findings with ghose membranes probably do not reflect faithfully the antigen arrangement on the intact red cell membrane.

scholarly journals The State of Water in Human and Dog Red Cell Membranes

1970 ◽  
Vol 55 (4) ◽  
pp. 451-466 ◽  
Author(s):  
F. L. Vieira ◽  
R. I. Sha'afi ◽  
A. K. Solomon
Keyword(s):  
Activation Energy ◽  
Cell Membrane ◽  
Apparent Activation Energy ◽  
Water Diffusion ◽  
Red Cells ◽  
Red Cell ◽  
Kcal Mole ◽  
Red Cell Membrane ◽  
Temperature Range ◽  
Human Red Cells

The apparent activation energy for the water diffusion permeability coefficient, Pd, across the red cell membrane has been found to be 4.9 ± 0.3 kcal/mole in the dog and 6.0 ± 0.2 kcal/mole in the human being over the temperature range, 7° to 37°C. The apparent activation energy for the hydraulic conductivity, Lp, in dog red cells has been found to be 3.7 ± 0.4 kcal/mole and in human red cells, 3.3 ± 0.4 kcal/mole over the same temperature range. The product of Lp and the bulk viscosity of water, η, was independent of temperature for both dog and man which indicates that the geometry of the red cell membrane is not temperature-sensitive over our experimental temperature range in either species. In the case of the dog, the apparent activation energy for diffusion is the same as that for self-diffusion of water, 4.6–4.8 kcal/mole, which indicates that the process of water diffusion across the dog red cell membrane is the same as that in free solution. The slightly, but significantly, higher activation energy for water diffusion in human red cells is consonant with water-membrane interaction in the narrower equivalent pores characteristic of these cells. The observation that the apparent activation energy for hydraulic conductivity is less than that for water diffusion across the red cell membrane is characteristic of viscous flow and suggests that the flow of water across the membranes of these red cells under an osmotic pressure gradient is a viscous process.

Cyclic Loading on the Red Cell Membrane in a Shear Flow: A Possible Cause of Hemolysis

1985 ◽  
Vol 107 (2) ◽  
pp. 91-95 ◽  
Author(s):  
H. Niimi ◽  
M. Sugihara
Keyword(s):  
Cyclic Loading ◽  
Cell Membrane ◽  
Shear Flow ◽  
Red Cells ◽  
Red Cell ◽  
Two Dimensional ◽  
Shear Forces ◽  
Red Cell Membrane ◽  
Possible Cause ◽  
Human Red Cells

The fluid force acting on single human red cells in a high shear flow was analyzed. A two-dimensional elliptical microcapsule as a model of the deformed red cells was adopted to numerically calculate the distributions of the shear forces on both sides of the cell membrane. It is theoretically shown that the cell membrane undergoes an unsteady cyclic loading under the rotational motion around the interior. The mechanism leading to blood cell trauma is examined by repeatedly loading the continuously moving cell membrane.

Effect of N-ethylmaleimide on K transport in density-separated human red blood cells

1987 ◽  
Vol 253 (1) ◽  
pp. C7-C12 ◽  
Author(s):  
L. R. Berkowitz ◽  
D. Walstad ◽  
E. P. Orringer
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Red Cells ◽  
Sheep Red Cells ◽  
Human Red Blood Cells ◽  
High K ◽  
K Transport ◽  
Human Red Cells

N-ethylmaleimide (NEM) is a sulfhydryl-reacting agent known to stimulate chloride-dependent K transport in a variety of red cells. In high K sheep red cells, NEM-induced K movements are greater in magnitude in young cells compared with old cells. We hypothesized that human red cells might respond to NEM like high K sheep red cells. To test this idea, cells of various age were exposed to 0.5 mM NEM. We found that, after a 4-h incubation, young cells lost 50% of cell K, compared with 10% K loss in older cells. K loss in all fractions was inhibited by chloride replacement or furosemide.

scholarly journals Reflection coefficients of permeant molecules in human red cell suspensions.

1975 ◽  
Vol 66 (2) ◽  
pp. 251-265 ◽  
Author(s):  
J D Owen ◽  
E M Eyring
Keyword(s):  
Molar Volume ◽  
Cell Suspensions ◽  
Red Cells ◽  
Stopped Flow ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Experimental Procedure ◽  
Rapid Flow ◽  
Coefficient Omega ◽  
Human Red Cells

The Staverman reflection coefficient, sigma for several permeant molecules was determined in human red cell suspensions with a Durrum stopped-flow spectrophotometer. This procedure was first used with dog, cat, and beef red cells and with human red cells. The stopped-flow technique used was similar to the rapid-flow method used by those who originally reported sigma measurements in human red cells for molecules which rapidly penetrate the red cell membrane. The sigma values we obtained agreed with those previously reported for most of the slow penetrants, except malonamide, but disagreed with all the sigma values previously reported for the rapid penetrants. We were unable to calculate an "equivalent pore radius" with our sigma data. The advantages of our equipment and our experimental procedure are discussed. Our sigma data suggest that sigma is indirectly proportional to the log of the nonelectrolyte permeability coefficient, omega. Since a similar trend has been previously shown for log omega and molar volume of the permeant molecules, a correlatioo was shown between sigma and molar volume suggesting the membrane acts as a sieve.

scholarly journals ELECTROPHORETIC STUDIES ON HUMAN RED BLOOD CELLS

1941 ◽  
Vol 24 (4) ◽  
pp. 447-457 ◽  
Author(s):  
Robert F. Furchgott ◽  
Eric Ponder
Keyword(s):  
Ionic Strength ◽  
Phosphate Buffer Solution ◽  
Strong Acid ◽  
Red Cells ◽  
Radius Of Curvature ◽  
Large Radius ◽  
Buffer Solution ◽  
Mobility Data ◽  
Human Red Blood Cells ◽  
Human Red Cells

1. The electrophoretic mobility of unhemolyzed human red cells has been determined as a function of ionic strength at approximately constant pH in isotonic mixtures of glucose solution and saline-phosphate buffer solution. 2. Above an ionic strength of about 0.02 the cells behave as particles with a smooth surface of large radius of curvature. Below an ionic strength of about 0.02, changes of the surface occur, probably involving a decrease of charge density and perhaps connected with injury of the surface. 3. The mobility as a function of pH at an ionic strength of 0.172 has been determined for human red cells, for the lipid extract of the cells, and for the stroma protein of the cells. The isoelectric points of cells, lipid, and protein have been found to be about 1.7, 2.6, and 4.7 respectively. 4. The pH-mobility data lead to the conclusion that a red cell surface is composed largely of lipid and dominated by strong acid groups, possibly the phosphoric acid groups of cephalin molecules.

Anion-dependent cation transport in erythrocytes

1982 ◽  
Vol 299 (1097) ◽  
pp. 483-495 ◽  
Keyword(s):  
Kinetic Data ◽  
Cation Transport ◽  
Red Cells ◽  
Transport Systems ◽  
Transport Pathway ◽  
Transport Pathways ◽  
Saturation Kinetics ◽  
High Concentrations ◽  
Dependent Transport ◽  
Human Red Cells

A selective survey of the literature reveals at least three major anion-dependent cation transport systems, defined as Na + + Cl - , K + + Cl - and Na + + K + + Cl - respectively. In human red cells, kinetic data on the fraction of K + and Na + influx inhibitable by bumetanide are presented to indicate an Na + :K + stoichiometry of 1:2. For LK sheep red cells the large Cl - -dependent K + leak induced by swelling is shown to share many characteristics with that induced by A-ethyl maleimide (NEM) treatment. NEM has complex effects, both inhibiting and then activating Cl “-dependent K+ fluxes dependent on NEM concentration. The alloantibody anti-L can prevent the action of NEM. In human red cells NEM induces a large Cl - -dependent specific K + flux, which shows saturation kinetics. Its anion preference is Cl - > Br - > SCN - > I - > NO - > 3 MeSO - 4 . This transport pathway is not inhibited by oligomycin or SITS, although phloretin and high concentrations of furosemide and bumetanide (over 0.3 mM) do inhibit. Quinine (0.5 mM) is also an inhibitor. It is concluded that at least two distinct Cl - -dependent transport pathways for K + are inducible in mammalian red cells, although the evidence for their separation is not absolute.

scholarly journals 506 IDENTIFICATION OF INHERITED PROTEIN VARIANTS IN CELLS INDIVIDUAL HUMAN RED CELLS

1978 ◽  
Vol 12 ◽  
pp. 448-448
Author(s):  
Stephen I O Anyaibe ◽  
Syama P Bhattacharya ◽  
Verle E Headings
Keyword(s):  
Red Cells ◽  
Protein Variants ◽  
Individual Human ◽  
Human Red Cells ◽  
In Cells
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