The transport of phosphate ions across the human red cell membrane II. The influence of the concentration of inorganic phosphate on the kinetics of the uptake of [32P]phosphate ions

1963 ◽  
Vol 66 ◽  
pp. 93-109 ◽  
Author(s):  
B. Vestergaard-Bogind
Keyword(s):  
Cell Membrane ◽  
Inorganic Phosphate ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Phosphate Ions ◽  
Kinetics Of ◽  
Human Red Cell Membrane

scholarly journals EVIDENCE OF ACTIVE TRANSFER OF CERTAIN NON-ELECTROLYTES ACROSS THE HUMAN RED CELL MEMBRANE

1948 ◽  
Vol 31 (6) ◽  
pp. 505-527 ◽  
Author(s):  
Paul G. LeFevre
Keyword(s):  
Cell Membrane ◽  
Sulfhydryl Group ◽  
Red Cell ◽  
Volume Changes ◽  
Red Cell Membrane ◽  
Simple Diffusion ◽  
Active Transfer ◽  
Saline Solutions ◽  
Kinetics Of ◽  
Human Red Cell Membrane

1. Permeability of the human erythrocyte to glycerol, as indicated by the course of hemolysis and volume changes, is depressed by Cu++, Hg++, I2, p-chloromercuribenzoate, and phlorhizin, without effecting general permeability changes. In so far as tested (Cu++, p-ClHgB), these inhibitors delay exit of glycerol from the cell as well as its entry. 2. Permeability to glucose is similarly depressed by I2 and phlorhizin, and is extremely sensitive to Hg++ and p-chloromercuribenzoate, but is not affected by Cu++. An extensive series of other enzyme poisons is without effect in either system. 3. The effects of the sulfhydryl inhibitors are prevented or reversed in the presence of glutathione, cysteine, etc. 4. The kinetics of the volume changes in glucose-saline solutions indicates a mechanism for transport of glucose into the cell, regulated by the existing intracellular concentration, rather than by simple diffusion gradients. 5. The intermediation of a sulfhydryl group at the cell surface, probably an enzymatic phosphorylation, is suggested as an essential step in the passage of glycerol, glucose, and other like substances, across the human red cell membrane.

scholarly journals Kinetics of bicarbonate-chloride exchange across the human red blood cell membrane.

1976 ◽  
Vol 68 (6) ◽  
pp. 633-652 ◽  
Author(s):  
E I Chow ◽  
E D Crandall ◽  
R E Forster
Keyword(s):  
Cell Membrane ◽  
Time Course ◽  
Transmembrane Potential ◽  
Arrhenius Plot ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Chloride Exchange ◽  
Kinetics Of ◽  
Exchange Flux ◽  
Human Red Cell Membrane

The kinetics of bicarbonate-chloride exchange across the human red cell membrane was studied by following the time course of extracellular pH in a stopped-flow rapid-reaction apparatus during transfer of H+ into the cell by the CO2 hydration-dehydration cycle, under conditions where the rate of the process was determined by HCO3--Cl- exchange flux across the membrane. The flux of bicarbonate increased linearly with [HCO3-] gradient from 0.6 to 20 mM across the red cell membrane at both 37 degrees C and 2 degrees C, and decreased as transmembrane potential was increased by decreasing extracellular [Cl-]. An Arrhenius plot of the rate constants for the exchange indicates that the Q10 is strongly dependent on temperature, being about 1.7 between 24 degrees C and 42 degrees C and about 7 between 2 degrees C and 12 degrees C. These data agree well with the published values for Q10 of 1.2 between 24 degrees C and 40 degrees C and of 8 between 0 degrees C and 10 degrees C. The results suggest that different processes may determine the rate of HCO3--Cl- exchange at low vs. physiological temperatures, and that the functional (and/or structural) properties of the red cell membrane vary markedly with temperature.

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