Observations on the Measurement and Regulation of the Sodium Content of Human Erythrocytes

1972 ◽  
Vol 42 (4) ◽  
pp. 447-453 ◽  
Author(s):  
E. K. M. Smith
Keyword(s):  
Linear Correlation ◽  
Sodium Pump ◽  
Potassium Concentration ◽  
Normal Subjects ◽  
Sodium Concentration ◽  
Sodium Content ◽  
Active Sodium ◽  
Sodium Efflux ◽  
Precise Control ◽  
A Cell

1. The sodium concentration within the erythrocytes of 159 subjects was found to be 7·35 ± 1·25 (SD) mmol/litre of cells. 2. In 157 normal subjects, the erythrocyte potassium concentration was 99·08 ± 5·3 (SD) mmol/litre of cells. 3. In the erythrocytes from twenty-seven normal subjects there was a striking linear correlation between the rate constant for active sodium efflux and resting sodium concentration. 4. It is concluded that these studies confirm the assumption that the resting concentration of sodium within a cell is determined by the activity of the sodium pump. What is not known is the mechanism by which this precise control is maintained.

Abnormalities in the Sodium Pump of Erythrocytes from Patients with Hyperthyroidism

1970 ◽  
Vol 38 (1) ◽  
pp. 49-61 ◽  
Author(s):  
E. K. M. Smith ◽  
Pamela D. Samuel
Keyword(s):  
Sodium Pump ◽  
Sodium Concentration ◽  
Intracellular Sodium ◽  
Red Cells ◽  
Control Group ◽  
Active Sodium ◽  
Sodium Efflux ◽  
Control Subjects ◽  
Intracellular Sodium Concentration ◽  
The Mean

1. Intracellular cation composition has been measured in the red cells from twenty patients with hyperthyroidism. The mean concentration of sodium was 11·18 m-mole/l red cells; in sixty normal control subjects the mean red cell sodium level was 7·04 m-mole/l. The difference between these two groups was highly significant. There was no measurable difference between the potassium concentration and water content of red cells from thyrotoxic and control groups. 2. Measurements of active sodium efflux were carried out in red cells from ten hyperthyroid subjects and their matched controls. The rate constant for active sodium efflux was significantly lower in the patients than the control group. 3. The total amount of sodium actively pumped from red cells in 1 hr was significantly higher in the patients than the controls. 4. The total amount of sodium moving out of the red cells, both actively and by exchange diffusion, matched the total influx of sodium. This was true for control subjects and those with hyperthyroidism and this would support the view that the intracellular sodium concentration is constant and represents the result of a balance between influx and efflux. In hyperthyroidism this balance persists, but with an abnormally high intracellular sodium concentration. 5. There was a linear relationship between the cell sodium content and the active transport of sodium from the cell in control and hyperthyroid subjects. 6. Triiodothyronine did not produce any change in sodium transport by normal red cells in vitro. 7. It is concluded that there is a depression of the activity of the sodium pump in the red cells of hyperthyroid subjects. This allows the resting intracellular sodium concentration to rise until a new steady state is reached. Evidence is given that these changes are reversed when hyperthyroidism is corrected.

A Study In Vitro of the Sodium Pump in Fulminant Hepatic Failure

1978 ◽  
Vol 55 (4) ◽  
pp. 355-363 ◽  
Author(s):  
A. N. Alam ◽  
Lucilla Poston ◽  
S. P. Wilkinson ◽  
C. G. Golindano ◽  
R. Williams
Keyword(s):  
Fulminant Hepatic Failure ◽  
Hepatic Failure ◽  
Sodium Pump ◽  
Normal Subjects ◽  
Sodium Content ◽  
Atp Content ◽  
Efflux Rate ◽  
Sodium Efflux ◽  
Reduced Activity

1. The mechanism underlying the raised leucocyte sodium content in fulminant hepatic failure was studied by measurement of sodium fluxes, (Na+ + K+)-dependent adenosine triphosphatase activity, and leucocyte ATP content. 2. The rate constant for sodium efflux in the leucocytes was significantly reduced, and attributable to reduced activity of the enzyme (Na+ + K+)-ATPase. Leucocyte ATP content was not significantly different from that of control cells. 3. Incubation of cells from patients in the sera of normal subjects resulted in a reversal of these changes. Inhibition of the leucocyte sodium efflux rate constants and (Na+ + K+)-ATPase of normal cells was achieved by incubation in sera from patients. 4. We suggest that the raised sodium content of leucocytes in fulminant hepatic failure is attributable to a defective sodium pumping mechanism, possibly due to a circulating toxin.

Aorta Electrolytes of Hypotensive Potassium-Deficient Rats

1958 ◽  
Vol 195 (2) ◽  
pp. 445-447 ◽  
Author(s):  
S. Charles Freed ◽  
Shirley St. George ◽  
Ray H. Rosenman
Keyword(s):  
Blood Pressure ◽  
Potassium Concentration ◽  
Pressure Rise ◽  
Sodium Concentration ◽  
Sodium Content ◽  
Potassium Deficiency ◽  
Sodium Potassium ◽  
High Sodium ◽  
Blood Pressure Rise ◽  
Arterial Tone

The hypotension of potassium-deficiency is associated with a decrease in aorta potassium concentration, the sodium content remaining unchanged, resulting in a high sodium/potassium ratio. Loss of arterial tone may result and thus contribute to the lowering of blood pressure. Cortisone administration to such rats does not alter the low aorta potassium content but appreciably reduces the sodium concentration. The return to a more normal sodium/potassium ratio in the aorta following cortisone may restore the arterial tone and thus explain the blood pressure rise to normal levels.

Preliminary Observations on the Ionic Regulation of the Arctic Char Salvelinus Alpinus

1971 ◽  
Vol 55 (1) ◽  
pp. 213-222
Author(s):  
R. A. ROBERTS
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Potassium Concentration ◽  
Salvelinus Alpinus ◽  
Sodium Concentration ◽  
Sodium Content ◽  
Arctic Char ◽  
The Arctic ◽  
High Degree ◽  
Total Sodium

1. The degree of euryhalinity in a fresh-water resident population of the arctic char, Salvelinus alpinus, has been determined. 2. Although isolated in fresh water for c. 10000-12000 years these fish still show a high degree of salinity tolerance characteristic of their ancestral stock, but this is variably developed in individuals. 3. In fresh water, blood sodium concentration is regulated at 150 mM/l and chloride at 130 mM/l. These increase to 233 and 218 mm/l respectively in sea water. 4. Fish in sea water show a large increase in muscle sodium, although the potassium concentration is only slightly higher than that maintained in fresh water. The total sodium content of the fish reflects the increase observed in the intracellular and extracellular compartments. 5. The rate of sodium turnover in sea-water-adapted fish is some ten times higher than in fresh-water-adapted fish, although it is significantly lower than that observed in most sea-water-adapted teleosts.

scholarly journals Rapid decrease in cellular sodium and chloride content during cold incubation of cultured liver endothelial cells and hepatocytes

1997 ◽  
Vol 322 (3) ◽  
pp. 693-699 ◽  
Author(s):  
Elke R. GIZEWSKI ◽  
Ursula RAUEN ◽  
Michael KIRSCH ◽  
Irith REUTERS ◽  
Herbert DIEDERICHS ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Rat Hepatocytes ◽  
Chloride Content ◽  
Sodium Concentration ◽  
Sodium Content ◽  
Surprising Result ◽  
Sodium Influx ◽  
Sodium Efflux ◽  
Uw Solution ◽  
Liver Endothelial Cells

Hypothermia, as used for organ preservation in transplantation medicine, is generally supposed to lead to an intracellular accumulation of sodium, and subsequently of chloride, via inhibition of the Na+/K+-ATPase. However, on studying the cellular sodium concentration of cultured liver endothelial cells using fluorescence microscopy, we found a 55% decrease in the cellular sodium concentration after 30 min of cold incubation in University of Wisconsin (UW) solution. To confirm this surprising result, we set up a capillary electrophoresis method that allowed us to determine the cellular contents of inorganic cations and of inorganic anions. Using this method we measured a decrease in the cellular sodium content from 104±11 to 55±4 nmol/mg of protein, accompanied by a decrease in the chloride content from 71±9 to 25±5 nmol/mg of protein, after 30 min of cold incubation in UW solution. When the endothelial cells were incubated in cold Krebs–Henseleit buffer or in cold cell culture medium instead of UW solution, similar early decreases in cellular sodium and chloride contents were observed, thus excluding the possibility of the decreases being dependent on the preservation solution used. Furthermore, experiments with cultured rat hepatocytes yielded a similar decrease in sodium content during initiation of cold incubation in UW solution, so the decrease does not appear to be cell-specific either. These results suggest that, contrary to current opinion, sodium efflux predominates over sodium influx during the early phase of cold incubation of cells.

Observations on the Measurement and Regulation of the Sodium Content of Rabbit Erythrocytes: Evidence for a Single Sodium Pump

1972 ◽  
Vol 50 (8) ◽  
pp. 791-797 ◽  
Author(s):  
E. K. M. Smith ◽  
D. Farrington ◽  
L. Sydiuk
Keyword(s):  
Rate Constant ◽  
Sodium Pump ◽  
Ethacrynic Acid ◽  
Sodium Content ◽  
Red Cells ◽  
Red Cell ◽  
Sodium Efflux ◽  
A Value ◽  
Active Transport Mechanism ◽  
Sodium Dependent

We have studied the cation content of rabbit erythrocytes; for a group of 40 animals red cell sodium was 9.2 ± 2.7 (S.D.) mmol/1 of cells, while potassium was 112 ± 8.6 mmol/1. Cell sodium content rose as the animals aged, but there was always a wide concentration gradient across the cell wall. This gradient was maintained by an active sodium pump, inhibited by ouabain (10−4 M) and comparable to pump I in the human red cell. The rate constant for this process in 16 rabbits was 0.313 ± 0.07 (S.D.) h−1, a value similar to that seen in man. Ethacrynic acid (10−3 M) inhibited a further component of sodium efflux, the rate constant being 0.259 ± 0.015 (S.D.) h−1. This was superficially comparable to pump II as previously described in the human; on further study, however, it was found to be sodium dependent, but able to function in the absence of adenosine triphosphate and incapable of net up-hill transport. These findings indicate that there is only one active transport mechanism in the red cells of the rabbit, which is a useful model for study in comparison to the red cells of man.

Defective genetic control of sodium-pump density in manic depressive psychosis

1981 ◽  
Vol 11 (2) ◽  
pp. 257-263 ◽  
Author(s):  
Graham J. Naylor ◽  
Anne H. W. Smith
Keyword(s):  
Genetic Control ◽  
Sodium Pump ◽  
Genetic Defect ◽  
Normal Subjects ◽  
Sodium Concentration ◽  
Manic Depressive Psychosis ◽  
Manic Depressive ◽  
Series Of Experiments

SynopsisThe ability of lymphocytes from manic-depressive and normal subjects to produce new pump sites in response to increased cell sodium was compared in a series of experiments. Ethacrynate or different potassium concentrations were used to increase cell sodium concentration. The lymphocytes of manic depressives had a significantly reduced ability to produce new pump sites. It is suggested that this may be the genetic defect underlying manic depressive psychosis.

Water and Sodium Turnover in Coastal and Inlnad Populations of the Ash-Grey Mouse, in Western Austrlia

1981 ◽  
Vol 29 (4) ◽  
pp. 519 ◽  
Author(s):  
KD Morris ◽  
SD Bradshaw
Keyword(s):  
Urine Osmolality ◽  
Sampling Period ◽  
Sodium Concentration ◽  
Sodium Content ◽  
Turnover Rates ◽  
Coastal Habitat ◽  
Sodium Influx ◽  
Sodium Efflux ◽  
Water Influx ◽  
Water Efflux

The water and sodium turnovers of a coastal and an inland population of P. albocinereus were studied seasonally. Although the inland habitat receives considerably less rain and sodium than the coastal habitat, water turnover rates were significantly lower only in May and sodium turnover lower only in August. Water influx rates were lowest at both locations during the summer months, positively correlated with the water content of the vegetation and positively correlated with the amount of rain received in the 30 days before each sampling period. Water efflux rates were negatively correlated with urine osmolality. Sodium influx rates were highest during the summer months and were correlated with the sodium content of the vegetation but not with the sodium deposited in the study areas. Sodium efflux rates were positively correlated with the urine sodium concentration. During the dry months, water and sodium influxes are linked; this is not apparent during the wetter months. The utilization of arthropods for food during the summer months is seen as contributing to the maintenance of water balance during a period when the vegetation is low in water. Both populations breed in late spring, with young animals growing during the summer months, and water and sodium influx rates exceed efflux rates during this period.

scholarly journals EFFECTS OF POTASSIUM, SODIUM, AND AZIDE ON THE IONIC MOVEMENTS THAT ACCOMPANY ACTIVITY IN FROG NERVES

1958 ◽  
Vol 41 (6) ◽  
pp. 1187-1203 ◽  
Author(s):  
Tomoaki Asano ◽  
W. P. Hurlbut
Keyword(s):  
Potassium Concentration ◽  
Compound Action Potential ◽  
Sodium Concentration ◽  
Sodium Content ◽  
Bathing Solution ◽  
External Potassium ◽  
Rate Of Decline ◽  
Ionic Movements ◽  
Sodium And Potassium ◽  
Compound Action

Stimulation of intact or desheathed frog sciatic nerves produced an increase in the sodium content and a decrease in the potassium content of this tissue. In desheathed preparations the magnitudes of the changes in ionic contents decreased as the concentration of the potassium in the bathing solution was increased, while changing the external sodium concentration produced small effects on the ionic shifts. During tetanization, the rate of decline of the compound action potential also decreased as the external potassium concentration increased. Eliminating the activity respiration with 0.2 mM azide did not greatly modify the changes in sodium and potassium distribution that accompanied activity in either intact or desheathed nerves.

Erythrocyte Sodium and Potassium in Patients with Hypokalaemia

1983 ◽  
Vol 64 (2) ◽  
pp. 167-176 ◽  
Author(s):  
M. Cumberbatch ◽  
D. B. Morgan
Keyword(s):  
Potassium Concentration ◽  
Sodium Content ◽  
Potassium Content ◽  
Extracellular Potassium ◽  
Moderate Degree ◽  
Sodium Efflux ◽  
Erythrocyte Sodium ◽  
Curvilinear Relation ◽  
Sodium And Potassium

1. The erythrocyte content of sodium and of potassium were measured in 231 unselected patients with hypokalaemia, and together with net ouabain-sensitive sodium efflux in patients with severe hypokalaemia, before (20 patients) and during potassium repletion (14 patients). 2. The erythrocytes of the patients with hypokalaemia compared with control subjects had on average an increase in sodium content, a decrease in potassium content and a reduction in the rate constant of ouabain-sensitive sodium efflux. All three changes had a similar curvilinear relation to the concentration of potassium in plasma with relatively little change in the measured variable unless the plasma potassium was very low. 3. There was a similar curvilinear relation between the final sodium and potassium content of normal erythrocytes and the potassium concentration of the medium in which they were incubated for 48 h in vitro. 4. These results suggest that the changes in the sodium and potassium content of erythrocytes in hypokalaemia are due to a direct inhibiting effect of the hypokalaemia on the activity of the sodium pump. 5. In many patients with hypokalaemia of moderate degree the increase in erythrocyte sodium content was less than expected from the effect in vitro of a low extracellular potassium concentration. This finding suggests that a compensatory change, presumably an increase in the number of sodium pumps, is a common event even in moderate hypokalaemia.

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