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.

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 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.

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 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.

scholarly journals Chloride and sodium influx: a coupled uptake mechanism in the squid giant axon.

1979 ◽  
Vol 73 (6) ◽  
pp. 801-818 ◽  
Author(s):  
J M Russell
Keyword(s):  
Giant Axon ◽  
Squid Giant Axon ◽  
Uptake Mechanism ◽  
External Concentration ◽  
Sodium Influx ◽  
Unidirectional Fluxes ◽  
Chloride Influx

The squid giant axon was internally dialyzed while the unidirectional fluxes of either Cl or Na were measured. The effects of varying the internal or external concentration of either Na or Cl were studied. Chloride influx was directly proportional to the external Na concentration whereas Cl efflux was unaffected by changes of the external Na concentration between 0 and 425 mM. Neither Cl influx nor efflux were affected by changes of internal Na concentration over the range of 8-158 mM. After ouabain and TTX treatment a portion of the remaining Na influx was directly dependent on the extracellular Cl concentration. Furthermore, when the internal Cl concentration was increased from 0 to 150 mM, the influxes of Cl and Na were decreased by 14 and 11 pmol/cm2.s, respectively. The influx of both ions could be substantially reduced when the axon was depleted of ATP. The influxes of both ions were inhibited by furosemide but unaffected by ouabain. It is concluded that the squid axolemma has an ATP-dependent coupled Na-Cl co-transport uptake mechanism.

scholarly journals Significance of Addressal of Clinical Investigations of Kidney Functions in Recovery/Mortality of Certain COVID-19 Patients

2021 ◽  
Vol 14 (4) ◽  
pp. 1985-1991
Author(s):  
Bennet Angel
Keyword(s):  
Treatment Protocol ◽  
Chloride Ions ◽  
Present Observation ◽  
Potassium Ions ◽  
Clinical Investigations ◽  
Preliminary Study ◽  
Degree Of Association ◽  
Kidney Functions ◽  
Sodium And Potassium ◽  
Robust Protocol

Clinical management of COVID-19 patients through a robust protocol is key to the good recovery and reduced mortality of patients. Efficient kidney functions during treatment period can contribute for improvised recovery and reduced mortality of patients. Analysis of the kidney function among Recovered and Dead cases of COVID-19 was made to reveal the degree of association of kidney functions with the two categories of patients. 83.4% of recovered patients did not show hyper values of blood urea whereas 72.5% of dead patients showed hyper-urea level in blood. 88.8% of survivors showed non-hyper creatinine level of blood whereas only 40% of dead cases showed hyper creatine level. Strong degree of association of blood urea with recovery/mortality was observed. Sodium levels were seen to be low while potassium and chloride ions were seen to be high in COVID-19 individuals. Our preliminary study suggests that kidney functions especially the value of blood urea and creatinine need to be addressed during COVID-19 patients to ensure the best recovery and reduced mortality. After more number of case studies, the present observation could sensitize consideration for inclusion of addressal and treatment of kidney functions into treatment protocol against COVID-19. It was also interesting to observe that levels of sodium and potassium ions among Survivors and Dead cases have impacted function of the essential ion channels in patient’s physiology.

scholarly journals Tendency of Change in Water Quality of the Main Shirvan Collector Over a Long Period

2022 ◽  
Vol 8 (1) ◽  
pp. 61-70
Author(s):  
F. Allakhverdiyeva
Keyword(s):  
Salt Content ◽  
Oxygen Demand ◽  
Chloride Ions ◽  
Assessment Criteria ◽  
Total Hardness ◽  
Hydrochemical Regime ◽  
Long Period ◽  
Salinity Water ◽  
Sodium And Potassium

The article examines the tendency of changes in the hydrochemical regime of the water of the Main Shirvan collector over a long period of time and the suitability of the collector water for irrigation. Continuous laboratory analyzes performed between 2004 and 2019 were compared to 1986. According to experimental data, it was determined that the hydrochemical regime of the collector water is gradually improving, and the salt content is decreasing. The degree of mineralization of the collector water decreased by 2.3 times, the total hardness by 2.2 times, the number of chloride ions by 10.5 times, the number of calcium ions by 1.3 times, the number of magnesium ions by 2.8 times, the total number of cations sodium and potassium decreased by 3.9 times. For 2004–2019 biochemical oxygen consumption in collector water increased 7.9 times, chemical oxygen demand increased 7.5 times, and the number of suspended particles increased 9 times. The amount of iron ions in water decreased by 2 times, while the amount of aluminum and zinc did not change. The suitability of collector water for irrigation was determined according to 7 internationally accepted assessment criteria. Collector water is considered suitable for irrigation in accordance with 6 assessment criteria — the degree of salinity, irrigation coefficient, sodium sorption coefficient, potential salinity, water alkalinity index and percentage of sodium, as well as 1 criterion not suitable for irrigation — the percentage of magnesium. Collector water can be used to irrigate crops.

The Absorption of Sodium Ions by the Crayfish Astacus Pallipes Lereboullet

1960 ◽  
Vol 37 (3) ◽  
pp. 548-556
Author(s):  
J. SHAW
Keyword(s):  
Loss Rate ◽  
External Solution ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Ammonium Ions ◽  
External Concentration ◽  
Sodium Influx ◽  
Hydrogen Ion Concentration ◽  
Sodium Loss ◽  
Ammonium Compounds

1. The effect of various cations in the external solution on the sodium influx in the crayfish, Astacus pallipes, has been studied. 2. Potassium in concentrations up to 4 mM./l. has no significant effect on the sodium influx from 0.05 mM./l. NaCl solutions. 3. Calcium has no effect on the influx in concentrations up to 1 mM./l. At higher concentrations the influx may be reduced in some cases. 4. Magnesium generally increases the influx by about 30%. The effect is not related to the external concentration. 5. Ammonium ions reduce sodium influx. With an ammonium/sodium concentraton ratio of 20:1 the influx is reduced to about 20% of normal. Ammonium ions do not affect the sodium loss rate. 6. Simple substituted ammonium compounds have little effect on the influx. 7. The external hydrogen ion concentration reduces sodium influx if the pH is below 6. At pH 4 the influx is reduced to 20-30% of normal. A low pH does not decrease the rate of sodium loss. 8. The nature of the specific inhibition of sodium influx by ammonium ions is discussed. It is suggested that the ammonium ions interfere with a normal sodium ammonium exchange mechanism.

scholarly journals Comparison of Photassium and Sodium Uptake by Barley Roots at High and Low Salt Status

1968 ◽  
Vol 21 (5) ◽  
pp. 871 ◽  
Author(s):  
MG Pitman ◽  
AC Courtice ◽  
Barbara Lee
Keyword(s):  
Sodium Influx ◽  
Sodium Uptake ◽  
Low Salt ◽  
Net Uptake ◽  
Sodium And Potassium

Measurements are described of the uptake of sodium and potassium by barley roots at low salt status. It was found that initially there was little preference for potassium in the salt accumulated, but about 5 hr after the start of salt accumula� tion net uptake of sodium decreased markedly, and thereafter much more potassium was taken up than sodium. The roots reached salt saturation in about 24 hr. The decreased sodium uptake was due to a reduction in sodium influx.

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