Nanostructural Changes in the Cell Membrane of Gamma-Irradiated Red Blood Cells

1. The addition of blood serum displaces the optimum for agglutination of red blood cells in a salt-free medium to the reaction characteristic of flocculation of the serum euglobulin. 2. This effect is not due merely to a mechanical entanglement of the cells by the precipitating euglobulin, since at reactions at which the latter is soluble it protects the cells from the agglutination which occurs in its absence. 3. A combination of some sort appears therefore to take place between sheep cells and sheep, rabbit, and guinea pig serum euglobulin, and involves a condensation of the serum protein upon the surface of the red cell. 4. At the optimal point for agglutination of persensitized cells both mid- and end-piece of complement combine with the cells. 5. Agglutination is closely related to an optimal H ion concentration in the suspending fluid, and probably of the cell membrane, and not to a definite reaction in the interior of the cell.

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The reduction of nitroblue tetrazolium by red blood cells: a measure of red cell membrane antioxidant capacity and hemoglobin-membrane binding sites

Free Radical Research ◽

10.1080/10715760100300501 ◽

2001 ◽

Vol 34 (6) ◽

pp. 605-620 ◽

Cited By ~ 10

Author(s):

Afolorunso A. Demehin ◽

Omoefe O. Abugo ◽

Joseph M. Rifkind

Keyword(s):

Cell Membrane ◽

Antioxidant Capacity ◽

Red Blood Cells ◽

Binding Sites ◽

Blood Cells ◽

Membrane Binding ◽

Nitroblue Tetrazolium ◽

Red Cell ◽

Red Cell Membrane ◽

Membrane Binding Sites

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A Fickian diffusion transport process with features of transport catalysis. Doxorubicin transport in human red blood cells.

The Journal of General Physiology ◽

10.1085/jgp.78.4.349 ◽

1981 ◽

Vol 78 (4) ◽

pp. 349-364 ◽

Cited By ~ 103

Author(s):

M Dalmark ◽

H H Storm

Keyword(s):

Cell Membrane ◽

Red Blood Cells ◽

Blood Cells ◽

Transport Process ◽

Fickian Diffusion ◽

Orbital Interaction ◽

Diffusion Transport ◽

Lipid Domain ◽

Human Red Blood Cells ◽

Membrane Components

The transport of the antineoplastic drug doxorubicin (Adriamycin) in human red blood cells was investigated by measuring the net efflux from loaded cells. Previous data indicated that doxorubicin transport was a Fickian diffusion transport process of the electrically neutral molecule through the lipid domain of the cell membrane (Dalmark, 1981 [In press]). However, doxorubicin transport showed saturation kinetics and a concentration-dependent temperature dependence with nonlinear Arrhenius plots. The two phenomena were related to the doxorubicin partition coefficient between 1-octanol and a water phase. This relationship indicated that the two phenomena were caused by changes in the physiochemical properties of doxorubicin in the aqueous phase and were not caused by interaction of doxorubicin with cell membrane components. The physicochemical properties of doxorubicin varied with concentration and temperature because of the ability of doxorubicin to form polymers by self-association in aqueous solution like other planar aromatic molecules through pi-electron orbital interaction. The hypothesis is proposed that doxorubicin transport across cell membranes takes place by simple Fickian diffusion.

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Evaluation of a Simpler Technique for In-Vivo Labelling of Red Blood Cells with 99mTc

Nuklearmedizin ◽

10.1055/s-0037-1620926 ◽

1980 ◽

Vol 19 (01) ◽

pp. 22-24

Author(s):

R. P. Sapru ◽

V. K. Chopra ◽

R. R. Sharma ◽

P. L. Wahi ◽

M. M. Rehani

Keyword(s):

Cell Membrane ◽

Oral Dose ◽

Red Blood Cells ◽

Blood Cells ◽

Stannous Chloride ◽

Abdominal Mass ◽

Chloride Dihydrate ◽

Perfusion Studies ◽

In Vivo Labelling

The efficiency of labelling red blood cells with intravenously administered 99mTc04, by prior oral administration of stannous chloride dihydrate, has been evaluated. Optimum labelling occured 1 hr after the oral dose of 200 mg of SnCl2 · 2 H20 and 20 min after the intravenous injection of 99mTc04. The mechanism of labelling has been shown to be diffusion of 99mTc through the cell membrane followed by binding to haemoglobin in the presence of reducing agent. The in-vivo labelling technique has been found to be useful for the diagnosis of an abdominal mass and for static perfusion studies.

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Hemolytic action of potassium salts on dog red blood cells

AJP Cell Physiology ◽

10.1152/ajpcell.1983.244.5.c313 ◽

1983 ◽

Vol 244 (5) ◽

pp. C313-C317 ◽

Cited By ~ 41

Author(s):

J. C. Parker

Keyword(s):

Cell Membrane ◽

Potassium Channel ◽

Red Blood Cells ◽

Blood Cells ◽

Red Cell ◽

Potassium Salts ◽

Red Cell Membrane ◽

Potassium Flux ◽

Hemolytic Action ◽

Calcium Activated Potassium Channel

Recent demonstrations of chloride-associated passive potassium movements in red blood cells of humans, ducks, sheep, and toadfish prompted a reinvestigation of potassium permeability in dog red blood cells. Early observations of Davson (J. Physiol. London 101:265-283, 1942) had shown that replacement of chloride by nitrate and thiocyanate caused a greatly increased rate of potassium flux across the dog red cell membrane. This finding seemed at variance with results in other species in which chloride replacement caused a fall in potassium flux. The present data indicate that passive potassium movements in swollen dog red blood cells are chloride dependent and furosemide sensitive, as shown for the cells of other species. Davson's findings were demonstrated to be due to the inclusion of small quantities of calcium in the medium under circumstances that favored calcium entry into the cells, thus opening the calcium-activated potassium channel described by Gardos (Curr. Top. Membr. Transp. 10:217-277, 1978 and Nature London 279:248-250, 1979). Potassium movements through the latter channel were stimulated when chloride was replaced by more permeant anions, such as nitrate and thiocyanate, which also increased the rate of net potassium movements in valinomycin-treated cells.

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Deoxygenation-induced alterations in sickle cell membrane cholesterol exchange

AJP Cell Physiology ◽

10.1152/ajpcell.1995.269.5.c1105 ◽

1995 ◽

Vol 269 (5) ◽

pp. C1105-C1111 ◽

Cited By ~ 7

Author(s):

J. Kavecansky ◽

F. Schroeder ◽

C. H. Joiner

Keyword(s):

Cell Membrane ◽

Red Blood Cells ◽

Sickle Cell ◽

Blood Cells ◽

Total Sterol ◽

Membrane Cholesterol ◽

Unilamellar Vesicles ◽

Rbc Membrane ◽

Spicule Formation ◽

Small Unilamellar Vesicles

Changes in a membrane sterol exchange of sickle red blood cells (SS RBC) induced by deoxygenation were studied using the fluorescent cholesterol analogue dehydroergosterol (DHE). DHE uptake by SS RBC membrane was measured by the incubation of SS RBC with small unilamellar vesicles (SUV) containing DHE. Deoxygenation of SS RBC, but not normal RBC, increased the rate of DHE uptake. DHE membrane content after 5 h of incubation with SUV in the cell-to-SUV ratio of 1:1 (mol lipid) was 16.25 +/- 0.94 and 12.22 +/- 0.85% of total sterol for deoxygenated and oxygenated cells, respectively. Membrane spicules isolated from these deoxygenated SS RBC had three-fold higher DHE content, suggesting that the increased sterol exchange was localized to spicules. When isolated spicules were incubated with DHE-SUV directly, 91 +/- 3% of membrane sterol was rapidly exchanged, in contrast to intact RBC, in which a maximum of 33% of sterol could be exchanged. The results suggest that spicule formation in SS RBC alters membrane cholesterol structure, such that a domain of cholesterol that is normally nonexchangeable becomes readily exchangeable with exogenous sterol.

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