CARRIER MECHANISMS IN THE MOVEMENT OF IONS ACROSS POROUS AND LIQUID ION EXCHANGER MEMBRANES

1966 ◽  
Vol 137 (2 Biological Me) ◽  
pp. 759-776 ◽  
Author(s):  
Gerald M. Shean ◽  
Karl Sollner
Keyword(s):  
Ion Exchanger ◽  
Liquid Ion Exchanger ◽  
Carrier Mechanisms

Characteristics of basolateral Cl- transport by gastric surface epithelium in Necturus antral mucosa

1993 ◽  
Vol 264 (5) ◽  
pp. G910-G920 ◽  
Author(s):  
D. I. Soybel ◽  
M. B. Davis ◽  
L. Y. Cheung
Keyword(s):  
Nutrient Solution ◽  
Cell Membranes ◽  
Basolateral Membrane ◽  
Membrane Potentials ◽  
Gastric Antrum ◽  
Ion Exchanger ◽  
Surface Epithelium ◽  
Antral Mucosa ◽  
Liquid Ion Exchanger ◽  
Electrochemical Equilibrium

Conventional and ion-selective microelectrodes were used to characterize transport of Cl- across the basolateral cell membranes of gastric surface epithelium in isolated preparations of gastric antrum of Necturus. Conventional, voltage-sensing electrodes were used to evaluate changes in membrane potentials and resistances during removal of Cl- from the nutrient perfusate. Liquid ion exchanger Cl(-)-selective microelectrodes were constructed and validated to measure intracellular Cl- activity (aiCl). Our data indicate that 1) aiCl (range 12-25 mM) is close to that predicted if Cl- is distributed across the cell membranes by electrochemical equilibrium, 2) aiCl is not influenced by changes in luminal Cl- content but is susceptible to changes in nutrient Cl- content, 3) Cl- conductances cannot be detected in the basolateral membrane and changes in membrane potentials do not influence aiCl, and 4) Cl- accumulation across the basolateral membrane depends on Na+ and the level of [K+] in the nutrient solution. Inhibition of K(+)-dependent Cl- accumulation, in the absence of nutrient Na+ or in the presence of the inhibitor bumetanide, was demonstrated. These findings suggest that basolateral Na(+)-K(+)-Cl- cotransport is important in regulating cell Cl- levels in surface cells of the gastric antrum in Necturus.

Work-induced potassium changes in skeletal muscle and effluent venous blood assessed by liquid ion-exchanger microelectrodes

1976 ◽  
Vol 362 (1) ◽  
pp. 85-94 ◽  
Author(s):  
P. Hník ◽  
M. Holas ◽  
I. Krekule ◽  
N. Kříž ◽  
J. Mejsnar ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Venous Blood ◽  
Ion Exchanger ◽  
Liquid Ion Exchanger

Intracellular potassium and chloride activities measured with liquid ion exchanger microelectrodes

1970 ◽  
Vol 23 (3) ◽  
pp. 433-436 ◽  
Author(s):  
M.C. Cornwall ◽  
D.F. Peterson ◽  
Diana L. Kunze ◽  
J.L. Walker ◽  
A.M. Brown
Keyword(s):  
Ion Exchanger ◽  
Intracellular Potassium ◽  
Liquid Ion Exchanger

Thirty years of ion-selective microelectrodes: disappointments and successes

1987 ◽  
Vol 65 (5) ◽  
pp. 873-878 ◽  
Author(s):  
J. A. M. Hinke
Keyword(s):  
Design Problem ◽  
Ion Exchanger ◽  
Neutral Carrier ◽  
Intracellular Activity ◽  
Measuring Devices ◽  
Active Membrane ◽  
Controlled Conditions ◽  
Liquid Ion Exchanger

The need to know the intracellular activity of an ion and how it changes under controlled conditions is as important today as it was 30 years ago. In 1956, one could fabricate only a H+-selective microelectrode and with a tip size not much smaller than 100 μm. Today, one can fabricate microelectrodes selective to H+, Na+, K+, Cl−, HCO3−, Ca2+, or Mg2+ (plus others) and with active tips less than 1 μm. The reduction of active tip size can be attributed mainly to the introduction of liquid ion exchanger (LIX) and neutral carrier ligands. Unfortunately, the LIX microelectrodes, as currently fabricated, do not yet function optimally as reliable and stable electrochemical measuring devices. A durable bond between the active membrane and its insulated container continues to remain the major design problem even after 30 years of development.

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