The Absorption of Sodium Ions by the Crayfish, Astacus Pallipes Lereboullet

1959 ◽  
Vol 36 (1) ◽  
pp. 126-144 ◽  
Author(s):  
J. SHAW
Keyword(s):  
Uptake Rate ◽  
Equilibrium Concentration ◽  
Maximum Level ◽  
Sodium Concentration ◽  
Sodium Content ◽  
Sodium Balance ◽  
Sodium Ions ◽  
External Concentration ◽  
Sodium Influx ◽  
True Measure

1. The effects of external and internal sodium concentrations on the uptake of sodium ions by the crayfish, Astacus pallipes, has been studied. 2. The normal sodium influx, measured with 24Na, from O.3 mM /l. NaCl solution is 1.5 µM./10 g. body weight/hr. The rate of loss of sodium to de-ionized water has roughly the same value. 3. Net loss of sodium reduces the external sodium concentration required for sodium balance. The minimum equilibrium concentration is about 0.04 mM./l. NaCl. 4. The relation between the external sodium concentration and the sodium influx is non-linear. The influx has a maximum of about 10 µM./10 g./hr. at an external concentration of approx. 1 mM./l. 5. The 24Na influx is a true measure of the sodium uptake rate at low external concentrations. At higher concentrations the influx may exceed the uptake rate by some 20%. 6. Net loss of sodium increases the influx by three to five times. Loss of 5-10% of the total internal sodium increases the influx from the normal to the maximum level. A 1% change has a significant effect on the influx. Changes in the internal sodium content reflect changes of the blood sodium concentration. 7. A scheme is suggested whereby the external and internal sodium concentrations interact together on the influx to produce a self-regulating system which maintains the animal in sodium balance.

Studies on Sodium Balance in Gammarus Duebeni Lilljeborg and G. Pulex Pulex (L.)

1961 ◽  
Vol 38 (1) ◽  
pp. 1-15
Author(s):  
J. SHAW ◽  
D. W. SUTCLIFFE
Keyword(s):  
Loss Rate ◽  
Sea Water ◽  
Sodium Concentration ◽  
Sodium Balance ◽  
Nacl Solution ◽  
Uptake Mechanism ◽  
External Concentration ◽  
Sodium Influx ◽  
Low Concentrations ◽  
Sodium Loss

1. The mechanisms of sodium balance in Gammarus duebeni and G. pulex, adapted to various external concentrations, were compared. 2. G. duebeni could be adapted to live in 1 mm/l. NaCl solution and, in some cases, to concentrations down to 0.2 mM/l. G. pulex could survive in concentrations as low as 0.06 mM/l. 3. The sodium loss rate in G. duebeni adapted to 2% sea water was much higher than in G. pulex but was reduced to about the same level when the animals were adapted to low external concentrations. 4. In both species there was a non-linear relationship between sodium influx and the external sodium concentration. In G. duebeni the uptake mechanism was saturated at an external concentration of about 10 mM/l., whereas in G. pulex saturation was reached at a much lower concentration. The maximum rate of uptake was greater in G. duebeni than in G. pulex. 5. In both species adaptation to low concentrations involved a small increase in the sodium influx and a reduction in the loss rate. 6. The most important factor in the superiority of G. pulex over G. duebeni in surviving at low external concentrations is the high affinity for sodium displayed by the uptake mechanism in G. pulex.

The Effect of Some Anions and Cations Upon the Fluxes and Net Uptake of Sodium in the Larva of Aedes Aegypti (L)

1965 ◽  
Vol 42 (1) ◽  
pp. 29-43 ◽  
Author(s):  
R. H. STOBBART
Keyword(s):  
Sodium Concentration ◽  
Sodium Content ◽  
Deionized Water ◽  
Sodium Balance ◽  
Sodium Influx ◽  
Sodium Uptake ◽  
Chloride Uptake ◽  
Net Uptake ◽  
The Relationship ◽  
Anal Papillae

1. Starved 4th-instar larvae of Aädes aegypti, when put into deionized water at a density of ten larvae/20 ml., are able to achieve sodium balance at the low external concentration of 5µM Na/l. 2. The balancing process involves a 10% drop in total sodium content, a more or less complete activation of the mechanism for sodium transport, and a reduction in the permeability of the larva to sodium as measured by the net sodium loss into deionized water. It is very probable that most of this reduction occurs in the anal papillae. 3. The relationship between external sodium concentration and sodium influx in larvae previously ‘balanced’ in deionized water is described approximately by the Michaelis equation. The sodium outflux also increases with increasing external sodium concentrations. 4. The net uptake of sodium by ‘balanced larvae’ appears to be significantly greater from solutions of NaCl than from solutions of NaNO3 NaHCO3 and Na2SO4. 5. The ions K+ Ca++ Mg++ and NH4+ when present as chlorides stimulate the influx of sodium from 0.1 mM/l. sodium chloride. When present as nitrates or sulphates they either have no effect or cause an inhibition of influx. 6. The results in 4 and 5 suggest that movements of chloride may be important in sodium uptake, and chloride uptake has been found to occur independently of sodium uptake. Measurements of potential difference between haemolymph and medium demonstrate active transport of both sodium and chloride.

The Sodium Balance Mechanism in the Fresh-Water Amphipod, Gammarus Lagustris Sars

1967 ◽  
Vol 46 (3) ◽  
pp. 519-528
Author(s):  
D. W. SUTCLIFFE ◽  
J. SHAW
Keyword(s):  
Fresh Water ◽  
Loss Rate ◽  
Sodium Concentration ◽  
The Body ◽  
Sodium Balance ◽  
External Concentration ◽  
Sodium Influx ◽  
Influx Rate ◽  
Sodium Loss ◽  
Balance Mechanism

1. The sodium balance mechanism of Gammarus lacustris in fresh water is virtually identical with that found in G. pulex. 2. The sodium transporting system at the body surface has a very high affinity for sodium ions. The system is half-saturated at an external concentration of about 0.14 mM/l. and fully saturated at about 1 mM/l. sodium. 3. The lowest external concentration at which sodium balance was maintained was 0.06 mM/l. 4. Both the total sodium loss rate and the sodium influx rate remained approximately constant in animals acclimatized to the range of external concentrations from 2 to 0.3 mM/l. NaCl. At lower concentrations the loss rate was reduced and the influx increased by a factor of about 1.5. 5. Changes in the sodium influx and loss rates are very closely linked together, and it is shown how these changes are related to the external sodium concentration.

Sodium Regulation in the Freshwater Mollusc Limnaea Stagnalis (L.) (Gastropoda: Pulmonata)

1970 ◽  
Vol 53 (1) ◽  
pp. 147-163 ◽  
Author(s):  
PETER GREENAWAY
Keyword(s):  
Blood Volume ◽  
Tap Water ◽  
Sodium Concentration ◽  
Sodium Balance ◽  
Uptake Mechanism ◽  
Sodium Influx ◽  
Sodium Uptake ◽  
Limnaea Stagnalis ◽  
Total Body ◽  
Sodium Regulation

1. Sodium regulation in normal, sodium-depleted and blood-depleted snails has been investigated. 2. Limnaea stagnalis has a sodium uptake mechanism with a high affinity for sodium ions, near maximum influx occurring in external sodium concentrations of 1.5-2 mM-Na/l and half maximum influx at 0.25 mM-Na/l. 3. L. stagnalis can maintain sodium balance in media containing 0.025 mM-Na/l. Adaptation to this concentration is achieved mainly by an increased rate of sodium uptake and a fall of 37 % in blood sodium concentration, but also by a reduction of the sodium loss rate and a decrease in blood volume. 4. A loss of 23% of total body sodium is necessary to stimulate increased sodium uptake. This loss causes near maximal stimulation of the sodium uptake mechanism. 5. An experimentally induced reduction of blood volume in L. stagnalis increases sodium uptake to three times the normal level. 6. About 40% of sodium influx from artificial tap water containing 0.35 mM-Na/l into normal snails is due to an exchange component. Similar exchange components of sodium influx were also observed in sodium-depleted and blood-depleted snails in the same external sodium concentration.

Studies on Fresh-Water Osmoregulation in the Ammocoete Larva of Lampetra Planeri (Bloch)

1970 ◽  
Vol 52 (2) ◽  
pp. 275-290
Author(s):  
R. MORRIS ◽  
J. M. BULL
Keyword(s):  
Sodium Concentration ◽  
Sodium Balance ◽  
Sodium Influx ◽  
Environmental Concentration ◽  
Carrier Mechanism ◽  
Controlling Mechanism ◽  
Lampetra Planeri ◽  
Reverse Situation ◽  
Sodium Loss ◽  
Term Response

1. Sodium influx in ammocoete larvae increases exponentially with external sodium concentration (0-1.0 mM/l.) and sodium-depleted animals show a 20% increase compared with normal animals. 2. Sodium loss decreases as the environmental concentration decreases, although the reverse situation is expected from considering diffusion outflux alone. 3. It is argued that part of the sodium loss is back-transported by the transport mechanism and this accounts for the reduced sodium loss from sodium-depleted animals whose sodium carrier activity is increased. The curves relating back-transport to environmental sodium differ from those derived by Kirschner for isolated frog skin. 4. Sodium influx increases as sodium loss increases, indicating a self mechanism whose features are discussed. In the ammocoete, the sodium carrier mechanism appears to change in affinity for sodium (short-term response) and can also change in concentration (long-term response), and it is suggested that these features, together with permeability changes, may form the basis of the controlling mechanism for sodium balance.

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.

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.

Studies on Ionic Regulation in Carcinus Maenas (L.)

1961 ◽  
Vol 38 (1) ◽  
pp. 135-152
Author(s):  
J. SHAW
Keyword(s):  
Body Weight ◽  
Sea Water ◽  
Carcinus Maenas ◽  
Sodium Concentration ◽  
Sodium Balance ◽  
Uptake Mechanism ◽  
Sodium Influx ◽  
Urine Production ◽  
Sodium Loss ◽  
Total Sodium

1. The mechanism of sodium balance in Carcinus maenas has been investigated. 2. Measurements of sodium outflux showed no evidence of a decrease in surface permeability to sodium in dilute sea water. 3. The rate of urine production in normal sea water was 3.6% body weight per day and the sodium loss through the urine was insignificant compared with the total sodium loss. In 40% sea water the urine rate was increased to 30% body weight per day and the loss in the urine accounted for 20% of the total loss. 4. Measurements of sodium influx and calculation of the active component showed that the active uptake mechanism was fully saturated at all external concentrations in which the animals could survive. 5. Regulation of the blood sodium concentration is effected largely by the activation of the sodium uptake mechanism. This prevents the blood concentration falling below a critical level as long as the external concentration itself is not too low.

The Effects of Chronic Hypokalaemia, Hyponatraemia, and Acid-Base Alterations on Erythrocyte Sodium Transport

1972 ◽  
Vol 43 (2) ◽  
pp. 251-263 ◽  
Author(s):  
M. L. Levin ◽  
F. C. Rector ◽  
D. W. Seldin
Keyword(s):  
Active Transport ◽  
Sodium Concentration ◽  
Sodium Content ◽  
Acid Base ◽  
Large Component ◽  
Sodium Influx ◽  
Membrane Function ◽  
Disease States ◽  
Erythrocyte Sodium

1. Erythrocyte sodium concentration and fluxes were measured in patients with acid-base disturbances, hypokalaemia and hyponatraemia. Results were similar to those obtained with normal erythrocytes exposed to artificial in vitro alterations. 2. Erythrocyte sodium content and influx varied directly with extracellular bicarbonate which appeared to influence membrane permeability. 3. Hypokalaemia increased the erythrocyte sodium content by decreasing active transport initially. When a new high erythrocyte steady-state sodium concentration was reached, active transport returned to normal but efflux and influx were increased considerably by the appearance of a large component of exchange diffusion in the hypokalaemic environment. 4. Hyponatraemia induced a decrease in sodium influx secondary to the decreased transmembrane sodium concentration gradient. A decrease in erythrocyte sodium content then ensued. 5. The results are discussed in relation to the assessment of cell membrane function in disease states.

Sodium Influx and Loss in Freshwater and Brackish-Water Populations of the Amphipod Gammarus Duebeni Lilljeborg

1971 ◽  
Vol 54 (1) ◽  
pp. 255-268
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Body Surface ◽  
Brackish Water ◽  
Sea Water ◽  
Sodium Concentration ◽  
The Body ◽  
Experimental Population ◽  
Sodium Ions ◽  
Sodium Influx ◽  
Wide Range ◽  
Freshwater Habitats

1. Sodium influx was examined in Gammarus duebeni from freshwater habitats on the Kintyre and Stranraer peninsulas in western Britain, and from a brackish-water habitat in Ireland. The affinity for sodium ions in the uptake mechanism at the body surface was similar in animals from the three localities. 2. Compared with the parent population from Kintyre, an experimental population established for 2 years in water with a lower sodium concentration showed an increased affinity for sodium. 3. Sodium losses in the urine of animals from the above localities were negligible at external salinities below about 2% sea water. In contrast, urinary sodium losses in animals from a brackish-water population in Britain were higher at salinities ranging from 40% sea water to well below 2% sea water. 4. The affinity for sodium ions in uptake mechanisms at the body surface and in the antennary glands of G. duebeni from a wide range of habitats shows a market correlation with the sodium concentration of the habitat. The permeability of the body surface to outward movement of sodium is similar in G. duebeni from brackishwater and freshwater habitats. 5. It is suggested that most of the observed physiological differences between populations of G. duebeni are phenotypic in origin. The status of the freshwater ‘race’ in Ireland is briefly discussed.

Sign in / Sign up

Export Citation Format

Share Document