Histamine selective microelectrode based on a synthetic organic liquid ion exchanger

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.

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

Pflügers Archiv - European Journal of Physiology ◽

10.1007/bf00588685 ◽

1976 ◽

Vol 362 (1) ◽

pp. 85-94 ◽

Cited By ~ 97

Author(s):

P. Hník ◽

M. Holas ◽

I. Krekule ◽

N. Kříž ◽

J. Mejsnar ◽

...

Keyword(s):

Skeletal Muscle ◽

Venous Blood ◽

Ion Exchanger ◽

Liquid Ion Exchanger

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Intracellular potassium and chloride activities measured with liquid ion exchanger microelectrodes

Brain Research ◽

10.1016/0006-8993(70)90070-3 ◽

1970 ◽

Vol 23 (3) ◽

pp. 433-436 ◽

Cited By ~ 16

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

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Increased Chloride Conductance As the Proximate Cause of Hydrogen Ion Concentration Effects in Aplysia Neurons

The Journal of General Physiology ◽

10.1085/jgp.56.5.559 ◽

1970 ◽

Vol 56 (5) ◽

pp. 559-582 ◽

Cited By ~ 57

Author(s):

A. M. Brown ◽

J. L. Walker ◽

R. B. Sutton

Keyword(s):

Organic Liquid ◽

Potassium Conductance ◽

Giant Cells ◽

Ion Exchanger ◽

Chloride Conductance ◽

Ion Concentration ◽

Equilibrium Potential ◽

Concentration Effects ◽

Hydrogen Ion Concentration ◽

Hyperpolarizing Response

A fall in extracellular pH increased membrane conductance of the giant cell in the abdominal ganglion of Aplysia californica. Chloride conductance was trebled whereas potassium conductance was increased by 50%. Half the giant cells were hyperpolarized (2–8 mv) and half were depolarized (3–10 mv) by lowering the pH. The hyperpolarizing response always became a depolarizing response in half-chloride solutions. When internal chloride was increased electrophoretically, the hyperpolarization was either decreased or changed to depolarization. The depolarizing response was reduced or became a hyperpolarizing response after soaking the cell in 10.0 mM chloride, artificial seawater solution for 1 hr. Depolarization was unaffected when either external sodium, calcium, or magnesium was omitted. A glass micropipette having an organic liquid chloride ion exchanger in its tip was used to measure intracellular chloride activity in 14 giant cells; 7 had values of 27.7 ± 1.8 mM (SEM) and 7 others 40.7 ± 1.5 mM. Three of the first group were hyperpolarized when pH was lowered and three of the second group were depolarized. In all six cells, these changes of membrane potential were in the direction of the chloride equilibrium potential. Intracellular potassium activity was measured by means of a potassium ion exchanger microelectrode.

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