Sodium and Potassium Transport Rates in Normal Human Leucocytes in Hypo-Osmolal Extracellular Fluid

1974 ◽  
Vol 46 (5) ◽  
pp. 613-617 ◽  
Author(s):  
P. J. Hilton ◽  
J. Patrick
Keyword(s):  
Rate Constants ◽  
Extracellular Fluid ◽  
Dry Weight ◽  
Potassium Transport ◽  
Sodium Influx ◽  
Potassium Efflux ◽  
Normal Human ◽  
Potassium Influx ◽  
Sodium And Potassium

1. Sodium and potassium transport rates were studied in normal human leucocytes exposed to iso-osmolal and hypo-osmolal extracellular fluid. 2. Hypo-osmolality of the extracellular fluid led to an increase in sodium influx and a decrease in potassium influx expressed as mmol h−1 kg−1 cell dry weight. The fall in potassium influx was smaller than the rise in sodium influx and was confined to the ouabain-insensitive portion of the flux. 3. The rate constants for sodium and potassium efflux did not differ significantly between the iso-osmolal and hypo-osmolal media.

Frusemide-Sensitive Sodium and Potassium Transport by Human Leucocytes

1985 ◽  
Vol 68 (1) ◽  
pp. 89-91 ◽  
Author(s):  
Valerie E. Johnson ◽  
P. J. Hilton
Keyword(s):  
Potassium Transport ◽  
Sodium Influx ◽  
Potassium Efflux ◽  
Sodium Potassium ◽  
External Potassium ◽  
Normal Human ◽  
Potassium Influx ◽  
Net Flux ◽  
Sodium And Potassium

1. Frusemide-sensitive sodium and potassium transport by normal human leucocytes has been studied in vitro by both isotopic and net flux techniques. 2. In physiological media the leucocyte exhibits a frusemide-sensitive influx of sodium and potassium of equal magnitude compatible with a 1:1 co-transport system. 3. Cells exposed to zero external sodium and potassium (osmolality maintained with choline) demonstrated a frusemide-sensitive sodium and potassium efflux. 4. Frusemide-sensitive potassium influx was dependent on the presence of external sodium but frusemide-sensitive sodium influx persisted unchanged in the absence of external potassium. 5. Frusemide-sensitive potassium influx was dependent on external chloride but frusemide-sensitive sodium influx was chloride-independent. 6. These last two observations make it likely that the frusemide-sensitive pathway is capable of operating in modes other than sodium-potassium co-transport.

Sodium and Potassium Flux Rates in Normal Human Leucocytes in an Artificial Extracellular Fluid

1973 ◽  
Vol 44 (5) ◽  
pp. 439-445 ◽  
Author(s):  
P. J. Hilton ◽  
J. Patrick
Keyword(s):  
Extracellular Fluid ◽  
Dry Weight ◽  
Radioactive Isotopes ◽  
Efflux Rate ◽  
Potassium Efflux ◽  
Sodium Efflux ◽  
Potassium Flux ◽  
Normal Human ◽  
Potassium Influx ◽  
Sodium And Potassium

1. Sodium and potassium efflux and influx rates were studied in normal human leucocytes in an artificial extracellular fluid using radioactive isotopes. 2. The rate constant for sodium efflux was 4.2 h−1 corresponding to a sodium efflux rate of 487 mmol kg cell dry weight−1 h−1. Approximately three-quarters of this flux was ouabain sensitive. 3. Potassium influx was 346 mmol kg cell dry weight−1 h−1. Approximately two-thirds of the potassium influx was ouabain insensitive.

Effect of Extracellular Potassium on the Transport of Sodium and Potassium in Rat Thymocytes

1981 ◽  
Vol 61 (3) ◽  
pp. 307-312 ◽  
Author(s):  
R. B. Jones ◽  
J. Patrick ◽  
P. J. Hilton
Keyword(s):  
Potassium Concentration ◽  
Extracellular Potassium ◽  
Sodium Influx ◽  
Potassium Efflux ◽  
Sodium Efflux ◽  
Extracellular Potassium Concentration ◽  
External Potassium ◽  
Potassium Influx ◽  
Sodium And Potassium

1. The effect of extracellular potassium on the transport of sodium and potassium in rat thymocytes has been studied in vitro. 2. A significant increase in the rate constant for total and ouabain-sensitive sodium efflux was demonstrated at an extracellular potassium concentration of 1 mmol/l as compared with that at either 0 or 2 mmol/l. 3. At potassium concentrations below 3 mmol/l ouabain-sensitive sodium influx was observed suggesting sodium-sodium exchange catalysed by the sodium pump. 4. Both total and ouabain-insensitive potassium efflux rose with external potassium. A small ouabain-sensitive potassium efflux was observed at all levels of external potassium studied. 5. Total and ouabain-insensitive potassium influx increased with external potassium, but did not appear to saturate. Ouabain-sensitive potassium influx reached a maximum at an external potassium concentration of 2 mmol/l then decreased with increasing external potassium.

The Effect of External Potassium Concentration on Leucocyte Cation Transport in Vitro

1975 ◽  
Vol 49 (5) ◽  
pp. 385-390
Author(s):  
P. J. Hilton ◽  
R. P. S. Edmondson ◽  
R. D. Thomas ◽  
J. Patrick
Keyword(s):  
Potassium Concentration ◽  
Potassium Transport ◽  
Potassium Efflux ◽  
Sodium Efflux ◽  
Maximum Value ◽  
External Potassium ◽  
Potassium Influx ◽  
Potassium Exchange ◽  
Sodium And Potassium

1. Sodium and potassium transport rates in human leucocytes were measured in vitro at different external potassium concentrations. 2. At nominally zero external potassium concentrations, the ouabain-sensitive sodium efflux was reduced to less than 20% of its maximum value. There was evidence that under these conditions a ouabain-sensitive sodium-sodium exchange occurs. 3. Both total and ouabain-insensitive potassium influx increased with increasing external potassium concentration. The ouabain-sensitive potassium influx showed saturation. 4. Ouabain-insensitive potassium efflux was also stimulated by increasing the external potassium concentration, suggesting significant potassium-potassium exchange at physiological external potassium concentrations.

Aldosterone and thyroid hormone interaction on the sodium and potassium transport pathways of rat colonic epithelium

1990 ◽  
Vol 124 (1) ◽  
pp. 47-52 ◽  
Author(s):  
C. J. Edmonds ◽  
C. L. Willis
Keyword(s):  
Electrical Potential ◽  
Dry Weight ◽  
Potassium Transport ◽  
Plasma Sodium ◽  
Electrical Potential Difference ◽  
Stimulant Effect ◽  
Potassium Adaptation ◽  
Short Period ◽  
Potassium Secretion ◽  
Sodium And Potassium

ABSTRACT The effect of hypothyroidism on potassium adaptation (shown by increased potassium secretion in response to potassium loading) and on the action of aldosterone on potassium secretion and sodium fluxes was examined in the rat distal colon. Potassium adaptation, particularly the response to an acute potassium load, was impaired by hypothyroidism which also considerably reduced the rise of transepithelial electrical potential difference (p.d.) of total and transcellular (active) lumen-to-plasma sodium fluxes and of potassium secretion normally produced by aldosterone. These changes were, in part, corrected by a short period (3 days) of tri-iodothyronine replacement. Moreover in aldosterone-treated hypothyroid rats, amiloride in the lumen was considerably less effective in reducing the p.d. and sodium fluxes than in aldosterone-treated normal rats. The intracellular sodium transport pool was greater in the hypothyroid than in the normal rats (5·0± 1·1 (s.e.m.) nmol/mg dry weight compared with 2·9 ± 0·2 nmol/mg dry weight; P<0·02). Aldosterone increased the pool in the normal but not in the hypothyroid rats while amiloride had little effect on the pool in the aldosterone-treated hypothyroid rats but almost abolished it in aldosterone-treated normal rats. Aldosterone plays a major part in the adaptation of colonic sodium and potassium transport to sodium depletion or potassium excess; these adaptations were much impaired in hypothyroid animals. The present results are consistent with a deficiency in aldosterone induction of potassium- and amiloride-sensitive sodium pathways in the apical membrane of colonic epithelial cells in hypothyroid rats, a deficiency which limits the stimulant effect of aldosterone on sodium and potassium transport. Journal of Endocrinology (1990) 124, 47–52

scholarly journals Sodium and Potassium Influx into Citrus Leaf Slices

1971 ◽  
Vol 24 (4) ◽  
pp. 861 ◽  
Author(s):  
FA Smith ◽  
JB Robinson
Keyword(s):  
Chloride Ions ◽  
External Concentration ◽  
Sodium Influx ◽  
Citrus Leaf ◽  
Potassium Influx ◽  
Citrus Leaves ◽  
Sodium And Potassium

The influxes of sodium and potassium have been measured in slices of mature citrus leaves, using 22Na and 42K as tracers. External concentrations were 0�03-100 mM (sodium) and 0�I-100 mM (potassium). The sodium influx was always less than the potassium influx, for any given external concentration. In neither case was the influx increased by light. There was no effect on the influxes when chloride ions in the experimental solutions were replaced by sulphate ions.

Use of Continuous Blood Volume Monitoring to Detect Inadequately High Dry Weight

1996 ◽  
Vol 19 (7) ◽  
pp. 411-414 ◽  
Author(s):  
F. Lopot ◽  
P. Kotyk ◽  
J. Bláha ◽  
J. Forejt
Keyword(s):  
Blood Volume ◽  
Vena Cava ◽  
Extracellular Fluid ◽  
Dry Weight ◽  
Whole Body ◽  
The Status ◽  
Varying Length ◽  
Group 3 ◽  
Group 2 ◽  
Total Body

A continuous blood volume monitoring (CBVM) device (Inline Diagnostics, Riverdale, USA) was used to study response to prescribed ultrafiltration during haemodialysis (HD) in 66 stabilised HD patients. Fifty percent of patients showed the expected linear decrease in BV right from the beginning of HD (group 1), 32% exhibited no decrease at all (group 2), while eighteen percent formed the transient group 3 which showed a plateau of varying length after which a decrease occurred. The correct setting of dry weight was verified through evaluation of the ratio of extracellular fluid volume to total body water (VEC/TBW) in 26 patients by means of whole body multifrequency impedometry MFI (Xitron Tech., San Diego, USA) and through measurement of the Vena Cava Inferior diameter (VCID) pre and post HD (in 6 and 5 patients from groups 1 and 3 and from group 2, respectively). The mean VEC/TBW in groups 1 and 3 was 0.56 pre and 0.51 post HD as compared to 0.583 and 0.551 in group 2. VCID decreased on average by 14.1% in groups 1 and 3 but remained stable in group 2. Both findings thus confirmed inadequately high estimation of dry weight. Since CBVM is extremely easy to perform it can be used as a method of choice in detecting inadequately high prescribed dry weight. The status of the cardiovascular system must always be considered before final judgement is made.

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