The influence of "nonmyoplasmic" sodium on the measured value of the sodium efflux from barnacle muscle

1981 ◽  
Vol 59 (12) ◽  
pp. 1219-1227 ◽  
Author(s):  
M. R. Menard ◽  
J. A. M. Hinke
Keyword(s):  
Extracellular Space ◽  
Striated Muscle ◽  
Muscle Cells ◽  
Sodium Content ◽  
Flame Photometry ◽  
Free Solution ◽  
Sodium Efflux ◽  
Barnacle Muscle ◽  
Total Sodium

In single striated muscle cells of the giant barnacle Balanus nubilus, the sodium content of the myoplasm was measured with an intracellular microelectrode, and the total sodium content of the cell was measured by flame photometry, during immersion of the cells in sodium-free solution. The sodium content of the myoplasm declined slowly but steadily from ca. 10 mmol/kg water to ca. 4 mmol/kg water during immersions lasting up to 16 h. The "nonmyoplasmic" sodium content of the cells, defined as the sodium content after subtraction of the sodium in the extracellular (sorbitol) space and in the myoplasm, declined rapidly from ca. 15 mmol/kg water to ca. 3 mmol/kg water during the first 30 min of immersion in sodium-free solution, but remained constant thereafter. The rapidly lost portion of the nonmyoplasmic sodium (ca. 12 mmol/kg water) was ascribed to the extracellular space but the location of the inexchangeable portion was not discovered. The behavior of the efflux of 22Na which was loaded into the myoplasm by microinjection was consistent with this interpretation. It was concluded that the nonmyoplasmic sodium does not have an appreciable influence on the measured value of the sodium efflux from the myoplasm of barnacle muscle cells.

External Ca effect on water permeability, regulatory volume decrease, and extracellular space in barnacle muscle cells

1993 ◽  
Vol 265 (4) ◽  
pp. C1128-C1137 ◽  
Author(s):  
D. M. Berman ◽  
C. Pena-Rasgado ◽  
M. Holmgren ◽  
P. Hawkins ◽  
H. Rasgado-Flores
Keyword(s):  
Water Permeability ◽  
Extracellular Space ◽  
Regulatory Volume Decrease ◽  
Three Dimensional ◽  
Muscle Cells ◽  
Barnacle Muscle ◽  
Dimensional Reconstruction ◽  
The Mean ◽  
The Relationship ◽  
Volume Decrease

The effect of extracellular Ca2+ (Cao) on sarcolemmal hydraulic water permeability (L'p), regulatory volume decrease (RVD), and extracellular space (ECS) was studied in barnacle muscle cells. Absence or presence of Cao had no effect on L'p [0 Cao = 2.762 +/- 0.098 x 10(-5), and 11 mM Cao = 2.720 +/- 0.222 x 10(-5) cm.kg.s-1 x osmol x 1-kgH2O-1]. Likewise, cells exposed to anisosmotic media (for < 30 min) behaved as osmometers in 0 and 11 mM Cao, showing similar slopes and intercepts in van't Hoff plots. At longer incubation times, however, hyposmotic conditions promoted a Cao-dependent RVD. The relationship between Cao and the percentage of cells responding with RVD to a hyposmotic challenge was sigmoidal (half-maximal Cao = 4.83 mM). The mean rate of RVD (40 nl/min) was independent of the level of swelling in response to hyposmotic challenges. However, the magnitude of RVD increased with larger hyposmotic challenges. Both the presence of Cao and hypotonicity reduced the "apparent" ECS by 47 +/- 6 and 39 +/- 6%, respectively. Three-dimensional reconstruction of autoradiographs of the cells was made to interpret these results.

Sodium exchange and net movement in rat uteri at 25 °C

1970 ◽  
Vol 48 (9) ◽  
pp. 598-624 ◽  
Author(s):  
E. E. Daniel ◽  
Kathleen Robinson
Keyword(s):  
Diffusion Coefficient ◽  
Time Course ◽  
Sodium Content ◽  
Free Solution ◽  
Electrochemical Gradient ◽  
Efflux Rate ◽  
Fresh Tissue ◽  
Sodium Efflux ◽  
Na Efflux ◽  
Wet Weight

Sodium fluxes in fresh and Na-rich uterine horns were studied. The change in efflux rate was compared with that in a theoretical model and analyzed by a curve-peeling technique. In both fresh and Na-rich tissues, the time course of efflux could be described by the sum of three exponentials. There was also a nearly inexchangeable ('bound') fraction of labelled sodium and a fraction of unlabelled sodium. Analysis of efflux led to the following equations:[Formula: see text]for fresh tissue, and[Formula: see text]for Na-rich tissues, where Y = tissue 22Na in millimoles per kilogram. The unlabelled part of the 'bound' Na amounted to 4 to 6 mmoles/kg in fresh and 6 to 8 mmoles/kg in Na-rich tissues. The amounts of 22Na in cells were calculated to be 7 and 34 mmoles/kg wet weight in fresh and Na-rich tissues. One phase of influx was similar to the fastest fraction of efflux and had a diffusion coefficient which was consistent with diffusion in the extracellular space (1/10 of that in free solution). The sodium content of this compartment was somewhat greater than sodium in the 14C-sucrose spaces (430 and 480 ml/kg in fresh and Na-rich tissue respectively). The second fastest sodium fraction (observed during efflux) was much larger in Na-rich tissues, and evidence that it contained cellular sodium was presented. Sodium efflux from cells was 5.9 pmoles cm−2 s−1 for fresh tissues and 26 pmoles cm−2 s−1 for Na-rich tissues. Comparable but less accurate values for influx were 4.2 and 7.0 pmoles cm−2 s−1. Assuming all emerging sodium was pumped against the electrochemical gradient, the energy expenditure would be 0.11 kcal/kg per h in fresh tissue and 0.22 kcal/kg per h in Na-rich tissues. It was concluded that this kind of active transport provides an unsatisfactory explanation for 22Na efflux.

Effects of Temperature on Branchial Sodium-Exchange and Extrusion Mechanisms in the Seawater-Adapted Flounder Platichthys Flesus L

1972 ◽  
Vol 56 (3) ◽  
pp. 565-585
Author(s):  
J. MAETZ ◽  
D. H. EVANS
Keyword(s):  
Sodium Content ◽  
Sodium Balance ◽  
Irreversible Damage ◽  
Simple Diffusion ◽  
Sodium Efflux ◽  
Temperature Changes ◽  
Platichthys Flesus ◽  
Sodium Load ◽  
Sodium Extrusion ◽  
Total Sodium

1. The effects of short-term and long-term temperature changes on the branchial components of sodium balance have been studied in the seawater-adapted flounder Platichthys flesus. 2. When fish adapted to 6°C are compared with fish adapted to 16°C a disturbance of sodium balance is observed; while the plasma level of sodium remains constant, an increased internal sodium space can be demonstrated isotopically. Increase of the muscle sodium content accounts for only a small part of the extra sodium content of the fish. The increased sodium load is the result of an impairment of the sodiumextrusion mechanism in the gills, and is demonstrated by the disappearance of the Na/K exchange activity of the gills. The passive sodium fluxes (by simple diffusion or exchange-diffusion) decrease only twofold. 3. Abrupt temperature changes in the 6-21°C temperature range are followed by instantaneous and reversible changes of the total sodium efflux (Q10 = 2), of the sodium leak observed after transfer into fresh water (Q10 = 1.7) and of the Na/Na exchange (Q10 = 2). The Na/K exchange, which corresponds presumably to the active sodium extrusion mechanism, shows in contrast a much greater temperature dependence (Q10 = 6). The total sodium efflux follows the Arrhenius relation between 6 and 21°C. 4. Abrupt transfer to higher temperatures (23-26 °C) produces irreversible damage to the transport system. 5. No compensatory acclimatization of the flux rates is observed during adaptation in the 6 °C environment. 6. The biological, physiological, ecological as well as biophysical implications of these findings are discussed. Particular emphasis is given to the problem of gill haemo-dynamics.

scholarly journals The Dual Effect of Lithium Ions on Sodium Efflux in Skeletal Muscle

1968 ◽  
Vol 52 (3) ◽  
pp. 408-423 ◽  
Author(s):  
L. A. Beaugé ◽  
R. A. Sjodin
Keyword(s):  
Skeletal Muscle ◽  
Muscle Cells ◽  
Sodium Concentration ◽  
Ringer Solution ◽  
Sodium Content ◽  
Sartorius Muscle ◽  
Lithium Ions ◽  
Sodium Efflux ◽  
Ringer’S Solution ◽  
Equivalent Quantity

Sartorius muscle cells from the frog were stored in a K-free Ringer solution at 3°C until their average sodium contents rose to around 23 mM/kg fiber (about 40 mM/liter fiber water). Such muscles, when placed in Ringer's solution containing 60 mM LiCl and 50 mM NaCl at 20°C, extruded 9.8 mM/kg of sodium and gained an equivalent quantity of lithium in a 2 hr period. The presence of 10-5 M strophanthidin in the 60 mM LiCl/50 mM NaCl Ringer solution prevented the net extrusion of sodium from the muscles. Lithium ions were found to enter muscles with a lowered internal sodium concentration at a rate about half that for entry into sodium-enriched muscles. When sodium-enriched muscles labeled with radioactive sodium ions were transferred from Ringer's solution to a sodium-free lithium-substituted Ringer solution, an increase in the rate of tracer sodium output was observed. When the lithium-substituted Ringer solution contained 10-5 M strophanthidin, a large decrease in the rate of tracer sodium output was observed upon transferring labeled sodium-enriched muscles from Ringer's solution to the sodium-free medium. It is concluded that lithium ions have a direct stimulating action on the sodium pump in skeletal muscle cells and that a significantly large external sodium-dependent component of sodium efflux is present in muscles with an elevated sodium content. In the sodium-rich muscles, about 23% of the total sodium efflux was due to strophanthidin-insensitive Na-for-Na interchange, about 67% being due to strophanthidin-sensitive sodium pumping.

Sodium activity of insect blood: physiological significance and relevance to the design of physiological saline

1975 ◽  
Vol 62 (3) ◽  
pp. 721-732
Author(s):  
J. E. Treherne ◽  
P. B. Buchan ◽  
R. R. Bennett
Keyword(s):  
Activity Coefficients ◽  
Periplaneta Americana ◽  
Physiological Saline ◽  
Sodium Content ◽  
Physiological Significance ◽  
Free Solution ◽  
Sodium Activity ◽  
The Face ◽  
Sodium And Potassium ◽  
Total Sodium

The apparent activity coefficients for sodium (gamma'Na) in the blood of six insect species have been calculated from measurements made with sodium-selective electrodes and a flame photometer. In every case gamma Na was significantly lower than that for this cation in free solution (gammaNa). In Periplaneta americana gammaNa varied considerably, during a period of 90 days, so that a relatively constant sodium activity (aNa) was maintained in the blood in the face of large variations in the total sodium content measured by flame photometry. Despite the relative constancy of aNa (of around 0.088M) appreciable fluctuations were observed in the sodium and potassium content of nervous connective over a period of 140 days. The values of aNa and aK were used to devise a satisfactory cockroach saline for use in experiments with isolated nerve cords.

Flame Photometry Characterization Procedure for Sodium Content in Brazilian Bentonites for Nanotechnology Applications

2019 ◽  
Vol 12 (2) ◽  
pp. 122-129
Author(s):  
Hellen S. Santos ◽  
Karine L. Buarque da Silva ◽  
Ariel E. Zanini ◽  
Danilo S. Coelho ◽  
Marcelo Embiruçu ◽  
...  
Keyword(s):  
Control Process ◽  
Sodium Concentration ◽  
High Water ◽  
Sodium Content ◽  
Industrial Applications ◽  
Exchange Capacity ◽  
Sodium Cation ◽  
Flame Photometry ◽  
Logarithmic Scale ◽  
Average Value

Background: Brazilian bentonites have a low sodium concentration in their interlayer structure. This is a problem with most of the industrial applications that demand the characteristics of sodium bentonites. Objective: As a solution for this limitation, sodium carbonate is added to in natura clays, promoting ion exchange between other interlayer cations with sodium. Methods: A process was used based on the principle of Stokes’ Law (BR Patent 10 2013 016298). For this, we used four glass columns in series, in which a high water flow was considered to obtain purified clays. It was proposed as a simple, fast and economical method for sodium determination that was developed and applied in bentonites by flame photometry. The equipment calibration was performed with a NaCl standard solution in concentrations between 80 and 110 ppm. The bentonites in the suspension were separated by means of centrifugation, being thus analyzed by a flame photometer. Results: The samples were prepared according to the manufacturer’s specifications to contain detectable amounts of sodium by means of flame photometry. A resulting linear relationship between the average value readings versus sodium standard content solution (both in ppm) was obtained by the logarithmic scale, as expected. Conclusion: The procedure allowed to define a method that could be used in the sodification control process, thus making it possible to differentiate the sodium cation content in terms of the value of cation exchange capacity (CEC) from bentonite. X-ray analysis of in natura and the sodified clays showed nanostructural differences related to interlayer distance.

scholarly journals Sodium intake and dietary sources of sodium in undergraduate students from Novi Sad, Serbia

2016 ◽  
Vol 73 (7) ◽  
pp. 651-656 ◽  
Author(s):  
Jelena Jovicic-Bata ◽  
Maja Grujicic ◽  
Slavica Radjen ◽  
Budimka Novakovic
Keyword(s):  
Undergraduate Students ◽  
Sodium Intake ◽  
Sodium Content ◽  
Bakery Products ◽  
Food Groups ◽  
High Sodium ◽  
Dietary Recall ◽  
Novi Sad ◽  
The University ◽  
Total Sodium

Background/Aim. Data on sodium intake and sources of sodium in the diet in Serbia are limited. The aim of this study was to estimate the sodium intake and identify the sources of sodium in the diet of undergraduate students attending the University of Novi Sad. Methods. Students completed a questionnaire to gather data on their gender, age and university faculty attended, and then a 24 h dietary recall. The sodium intake of the students was calculated using the dietary recall data and data on the sodium content of foods. The contribution of different food groups as well as of specific foodstuffs to the total sodium intake was calculated. Results. The mean estimated sodium intake of the students was 3,938.5 ? 1,708.1 mg/day. The sodium intake of 89.1% of the surveyed students exceeded the guideline for sodium intake, the majority of the sodium coming from processed foods (78.9% of the total sodium intake). The food groups that contributed the most to the total sodium intake of the students were meat and meat products (21.7%) and cereals and cereal-based products (18.6%). Bread and other bakery products were responsible for 13.1% of the total sodium intake. Conclusion. High sodium intake in students of the University of Novi Sad puts them at high risk of developing high blood pressure. The food industry should work towards reformulating products with high sodium content, especially bread and other bakery products. Efforts should be taken to reduce sodium intake among undergraduate students in Novi Sad.

scholarly journals The Ionic Basis of the Resting Potential in a Cross-Striated Muscle of the Aquatic Snail Lymnaea Stagnalis

1984 ◽  
Vol 108 (1) ◽  
pp. 305-314
Author(s):  
B. L. BREZDEN ◽  
D. R. GARDNER
Keyword(s):  
Membrane Potential ◽  
Lymnaea Stagnalis ◽  
Striated Muscle ◽  
Potassium Concentration ◽  
Muscle Cells ◽  
Resting Potential ◽  
Extracellular Potassium ◽  
Heart Ventricle ◽  
Sodium Permeability ◽  
Ionic Basis

The mean resting potential in the heart ventricle muscle cells of the freshwater snail Lymnaea stagnalis was found to be −61.2±3.5 (˙˙) mV (ranging from −56mV to −68mV). The average intracellular potassium concentration was estimated to be 51.5±14.6(˙˙) m (ranging from 27.8 m to 77.3 m). The membrane of the heart ventricle muscle cells appears to be permeable to both potassium and chloride, as changes in the extracellular concentration of either of these ions resulted in a change in the membrane potential. A ten-fold change in the extracellular potassium concentration was associated with a 50.4±3.8(˙˙) mV slope when the potassium concentration was above about 6 m. Deviations from the straight-line relation predicted for a potassium electrode could be accounted for by introducing a term for sodium permeability. The ionic basis of the membrane potential in these cells can be described by a modified form of the Goldman-Hodgkin- Katz equation.

scholarly journals A Novel Conserved Isoform of the Ubiquitin Ligase UFD2a/UBE4B Is Expressed Exclusively in Mature Striated Muscle Cells

PLoS ONE ◽  
2011 ◽  
Vol 6 (12) ◽  
pp. e28861 ◽  
Author(s):  
Andrew L. Mammen ◽  
James A. Mahoney ◽  
Amanda St. Germain ◽  
Nisha Badders ◽  
J. Paul Taylor ◽  
...  
Keyword(s):  
Ubiquitin Ligase ◽  
Striated Muscle ◽  
Muscle Cells
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