scholarly journals Sidedness of the effects of sodium and potassium ions on the conformational state of the sodium-potassium pump

1981 ◽  
Vol 312 (1) ◽  
pp. 505-529 ◽  
Author(s):  
S. J. D. Karlish ◽  
U. Pick
Keyword(s):  
Conformational State ◽  
Potassium Ions ◽  
Sodium Potassium ◽  
Sodium Potassium Pump ◽  
Sodium And Potassium

Evidence of Altered Permeability of the Erythrocyte Membrane for Sodium and Potassium ions in Spontaneously Hypertensive Rats

1976 ◽  
Vol 51 (s3) ◽  
pp. 169s-172s ◽  
Author(s):  
YU. V. Postnov ◽  
S. N. Orlov ◽  
P. V. Gulak ◽  
A. S. Shevchenko
Keyword(s):  
Erythrocyte Membrane ◽  
Spontaneously Hypertensive Rats ◽  
Potassium Ions ◽  
Sprague Dawley ◽  
Hypertensive Rats ◽  
Sodium Potassium ◽  
Spontaneously Hypertensive ◽  
Sprague Dawley Rats ◽  
Sodium Potassium Pump ◽  
Sodium And Potassium

1. Erythrocyte membrane permeability to sodium and potassium ions was studied in 8–10 weeks spontaneously hypertensive rats (SHR, Kyoto/Wistar strain), normotensive Wistar and Sprague—Dawley rats. 2. The rate of 22Na efflux from the erythrocytes and the rate constant of Na/Na exchange were considerably greater in SHR than in normotensive Wistar and Sprague—Dawley rats. This difference remained the same in rats adrenalectomized 7 days before the experiment. The maximum difference in the constants was found when the sodium—potassium pump was blocked by ouabain. 3. The accumulation of 42K in the erythrocytes of SHR (the sodium—potassium pump being blocked) took place at a considerably slower rate, and the K+ wash-out into a potassium-free medium was faster than that in the normotensive Wistar and Sprague—Dawley rats. 4. These results indicate a higher permeability of the erythrocyte membrane of SHR for Na+ and K+, compared with normotensive Wistar and Sprague—Dawley strains. It is suggested that this may reflect a more widespread cell-membrane defect, which could serve as a general cause for activating the mechanisms maintaining high blood pressure.

Reliability of the Hitachi sodium and potassium electrodes assessed.

1985 ◽  
Vol 31 (3) ◽  
pp. 457-459 ◽  
Author(s):  
P Winkel ◽  
M Wilken ◽  
J Christiansen ◽  
B Buch
Keyword(s):  
Electrode System ◽  
Potassium Ions ◽  
Sodium Potassium ◽  
Flame Photometer ◽  
Serum Pool ◽  
Sodium And Potassium

Abstract We compared the Hitachi 705 E sodium/potassium electrode system with the Radiometer flame photometer for measuring concentrations of sodium and potassium ions in serum and plasma. Our data show that the Hitachi results are slightly but significantly (less than 0.001) lower than the flame photometer results: Na+ 1.33 mmol/L for serum and 2.24 mmol/L for plasma; K+ 0.062 mmol/L for serum and 0.082 mmol/L for plasma. The magnitude of the bias varied considerably from day to day, ranging from -0.10 to 2.33 mmol/L for Na+ in serum and from 0.00 to 0.11 mmol/L for serum K+; for plasma specimens the corresponding ranges were -0.03 to 5.97 mmol/L and 0.00 to 0.17 mmol/L. These variations probably reflected difficulties in reproducing the calibration from day to day, because the daily means for a serum pool varied in parallel. We occasionally encountered serious problems with reproducibility.

scholarly journals Changes in the Membrane Permeability of Frog's Sartorius Muscle Fibers in Ca-Free EDTA Solution

1963 ◽  
Vol 47 (2) ◽  
pp. 379-392 ◽  
Author(s):  
H. Kimizuka ◽  
K. Koketsu
Keyword(s):  
Membrane Permeability ◽  
Chloride Content ◽  
Chloride Ions ◽  
Sartorius Muscle ◽  
Constant Field ◽  
Sodium Influx ◽  
Sodium Potassium ◽  
Edta Solution ◽  
Frog Sartorius ◽  
Sodium And Potassium

The changes in the membrane permeability to sodium, potassium, and chloride ions as well as the changes in the intracellular concentration of these ions were studied on frog sartorius muscles in Ca-free EDTA solution. It was found that the rate constants for potassium and chloride efflux became almost constant within 10 minutes in the absence of external calcium ions, that for potassium increasing to 1.5 to 2 times normal and that for chloride decreasing about one-half. The sodium influx in Ca-free EDTA solution, between 30 and 40 minutes, was about 4 times that in Ringer's solution. The intracellular sodium and potassium contents did not change appreciably but the intracellular chloride content had increased to about 4 times normal after 40 minutes. By applying the constant field theory to these results, it was concluded that (a) PCl did not change appreciably whereas PK decreased to a level that, in the interval between 10 and 40 minutes, was about one-half normal, (b) PNa increased until between 30 and 40 minutes it was about 8 times normal. The low value of the membrane potential between 30 and 40 minutes was explained in terms of the changes in the membrane permeability and the intracellular ion concentrations. The mechanism for membrane depolarization in this solution was briefly discussed.

Effect of palytoxin on the sodium–potassium pump: model and simulation

2008 ◽  
Vol 5 (3) ◽  
pp. 036005 ◽  
Author(s):  
Antônio M Rodrigues ◽  
Antônio-Carlos G Almeida ◽  
Antonio F C Infantosi
Keyword(s):  
Sodium Potassium ◽  
Model And Simulation ◽  
Sodium Potassium Pump
Sign in / Sign up

Export Citation Format

Share Document