Regulation of Water and Some Ions in Gammarids (Amphipoda)

1971 ◽  
Vol 55 (2) ◽  
pp. 345-355
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Water Content ◽  
Sea Water ◽  
Potassium Concentration ◽  
Body Water ◽  
The Body ◽  
Sodium Potassium ◽  
Intracellular Space ◽  
Body Sodium ◽  
The Mean ◽  
Total Body

1. The water content, and the concentrations of sodium potassium and chloride in the blood and body water were determined in Gammarus pulex acclimatized to external salinities ranging from 0.06 mM/l NaCl up to 50 % sea water. 2. The mean body water content remained constant at 79.0-80.3 % body wet weight. The total body sodium and chloride concentrations were lowered in 0.06 mM/l NaCl and increased markedly at salinities above 10% sea water. The normal ratio of body sodium/chloride was 1.45-1.70, decreasing to 1.0 at 50% sea water. 3. The total body potassium concentration remained constant at 47.5-55.2 mM/kg body H2O. The rate of potassium loss across the body surface was relatively fast. Potassium balance was maintained at an external potassium concentration of 0.005 mM/l by starved animals, and at 0.005 mM/l by fed animals. 4. The proportion of body water in the blood space was calculated from the concentrations of potassium and chloride in the blood and in the body water. The blood space contained 38-42% body H2O in animals from fresh water. The blood space decreased to 31 % body H2O in animals from 0.06 mM/l NaCl. The sodium space was equivalent to about 70 % body H2O. 5. The mean intracellular concentrations of sodium, potassium and chloride were estimated and the results were compared with previous analyses made on the tissues of G. pulex and other crustaceans. It was concluded that in G. pulex from fresh water the distribution of potassium and chloride ions between the extracellular blood space and the intracellular space approximately conforms to a Donnan equilibrium. 30-40% of the body sodium is apparently located in the intracellular space.

scholarly journals Regulation of Water and Some Ions in Gammarids (Amphipoda)

1971 ◽  
Vol 55 (2) ◽  
pp. 357-369
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Sodium Chloride ◽  
Sea Water ◽  
Chloride Concentration ◽  
Sodium Concentration ◽  
Body Water ◽  
The Body ◽  
Salinity Range ◽  
Sodium Potassium ◽  
Body Sodium ◽  
Total Body

1. A comparison was made of the body water contents and the concentrations of sodium, potassium and chloride in the blood and body water of Gammarus zaddachi, G. locusta and Marinogammarus finmarchicus. 2. G. zaddachi had a slightly higher body water content than G. locusta and M. finmarchicus. 3. In all three species the blood chloride concentration was lower than the external chloride concentration in 80-113 % sea water, but the blood sodium concentration was equal to or slightly above the sodium concentration in the external medium. 4. The total body sodium concentration was always greater than the total body chloride concentration. In M.finmarchicus the ratio of body sodium/chloride increased from 1.2 to 1.3 over the salinity range 100-20% sea water. In G. zaddachi the ratio of body sodium/chloride increased from 1.08 at 100% sea water to 1.87 in 0.25 mM/l NaCl. 5. The total body potassium concentration remained constant. The potassium loss rate and the balance concentration were relatively high in G. zaddachi. 6. The porportion of body water in the blood space was calculated from the assumption that a Donnan equilibrium exists between chloride and potassium ions in the extracellular blood space and the intracellular space. In G. zaddachi the blood space was equivalent to 60% body H2O at 100% sea water, and equivalent to 50% body H2O at 40% sea water down to 0.5 mM/l NaCl. In M.finmarchicus the blood space was equivalent to 38-44% body H2O at salinities of 20-100% sea water. 7. The mean intracellular concentrations of sodium, potassium and chloride were also calculated. It was concluded that for each ion its intracellular concentration is much the same in the four euryhaline gammarids. The intracellular chloride concentration is roughly proportional to the blood chloride concentration. The intracellular sodium concentration is regulated in the face of large changes in the blood sodium concentration.

Regulation of Water and Some Ions in Gammarids (Amphipoda)

1971 ◽  
Vol 55 (2) ◽  
pp. 325-344
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Brackish Water ◽  
Sea Water ◽  
Chloride Content ◽  
Chloride Ions ◽  
Body Water ◽  
The Body ◽  
Potassium Balance ◽  
Body Sodium ◽  
External Potassium ◽  
Total Body

1. Gammarus duebeni from brackish water was acclimatized to salinities ranging from 100% sea water down to 0.25 mM/1 NaCl at 9 °C. 2. The body water content increased from 76 to 81% body wet weight. The ratio of total body sodium/chloride increased from 1.04 to 1.52. The sodium space remained constant, equivalent to about 65 % body H2O. The chloride space decreased from about 60% body H2O down to 35% body H2O. 3. Total body potassium remained almost constant and showed only a small decrease in dilute NaCl-media. Potassium balance was maintained for several days at an external potassium concentration of 0.010-0.015 mM/1. 4. The proportion of body water in the extracellular blood space was calculated from the assumption that potassium and chloride ions were distributed in a Donnan equilibrium between the blood and intracellular spaces. The blood space was slightly smaller than the chloride space. 5. The mean intracellular concentrations of sodium, potassium and chloride were calculated. Sodium fell from 120 to 75 mM/kg cell H2O, potassium fell from 125 to 75 mM/kg cell H2O and chloride fell from 55 to 12 mM/kg cell H2O. These concentrations are similar to the concentrations found in the muscles of decapods and in the tissues of other animals. 6. About 10% of the body chloride and 93-97% of the body potassium is situated in the cells. The proportion of intracellular sodium increased from 17-18% body sodium at 100% sea water to 40-50% body sodium at 0.25 mM/l NaCl. 7. G. duebeni from three freshwater populations were acclimatized to 2 % sea water, 0.5 and 0.25 mM/l NaCl. The body surface is three times more permeable to potassium than it is to sodium and chloride. Potassium balance in starved animals was achieved at 0.010-0.015 mM/l K. Fed animals had a higher body sodium and chloride content than starved animals. 8. The regulation of body water and ions in animals from the freshwater populations was essentially the same as in animals from brackish-water populations. The significance of the results is discussed in relation to the process of adaptation to fresh water.

Estimation of water content by tritium dilution of animals subjected to rapid live-weight changes

1969 ◽  
Vol 72 (1) ◽  
pp. 31-40 ◽  
Author(s):  
W. R. McManus ◽  
R. K. Prichard ◽  
Carolyn Baker ◽  
M. V. Petruchenia
Keyword(s):  
Body Weight ◽  
Water Content ◽  
Total Body Water ◽  
Compensatory Growth ◽  
Specific Activity ◽  
Tritiated Water ◽  
Body Water ◽  
Under Nutrition ◽  
The Mean ◽  
Total Body

SUMMARYThe use of tritiated water to estimate total body-water content of animals experiencing recovery from under-nutrition was studied.The time for equilibration of tritiated water (TOH), given intraperitoneally, with total body water (TBW) was determined in rabbits and in rats. As judged by the specific activity of blood water, equilibration had occurred by 76–125 min in the rabbit and did not appear to be affected by the plane of nutrition. However, between slaughter groups the specific activity of water obtained from the liver 180 min after injection of TOH was significantly different from the specific activity of water simultaneously obtained from the blood plasma. It is concluded that the liver is not a suitable tissue to use for testing achievement of equilibration.As judged by the specific activity of blood water compared to that of water from the whole body macerate, equilibration in mature rats either in stable body condition or undergoing rapid compensatory growth occurred in less than 60 min.A trial comparing TOH-space (corrected by 3% body weight) and actual TBW (by desiccation) was conducted on thirty rabbits which experienced under-nutrition followed by compensatory growth.Prior to under-nutrition the agreement between actual and estimated TBW was satisfactory and within 2·3%. During compensatory growth the agreement was poor— the TOH values over-estimating actual TBW by about 12%.A trial with mature rats confirmed the findings with rabbits. For rats in stable body weight the mean estimated TOH-space for fourteen animals was within 1·2% of the actual TBW. For fourteen rats undergoing compensatory growth the mean estimated TOH-space (corrected by 3% body weight) overestimated actual TBW by 6·2%.

Effect of a chelating agent (EDTA) on zinc uptake and regulation by Palaemon elegans (Crustacea: Decapoda)

1988 ◽  
Vol 68 (1) ◽  
pp. 25-40 ◽  
Author(s):  
D. Nugegoda ◽  
P. S. Rainbow
Keyword(s):  
Sea Water ◽  
Chelating Agent ◽  
The Body ◽  
Zn Uptake ◽  
Zn Concentration ◽  
Zinc Concentrations ◽  
The Mean ◽  
Palaemon Elegans ◽  
Total Body ◽  
Body Concentration

The littoral prawn Palaetnon elegans Rathke regulates the body concentration of zinc at higher external zinc concentrations in the presence of EDTA. The dissolved zinc concentration in artificial sea water corresponding to the threshold of regulation breakdown changed from ca. 100 μg Zn 1-1 (ca. 1.53 μmol Zn 1-1) without EDTA, to ca. 316 μg Zn 1-1 (ca. 4.8 μmo1 Zn 1-1) in the presence of 8.6μmol EDTA 1-1 at 10 °C. The regulated body Zn concentration remained unchanged at 77–79 μg Zn g-1 dry wt with or without EDTA. Increased levels of EDTA in the medium decreased the rate of uptake of labelled zinc by P. elegans. The presence of 3 μmol EDTA 1-1 decreased the mean Zn uptake rate of prawns in 100 fig Zn 1-1 (ca. 1.53 μmol Zn 1-1) from 2.9 to 0.25% of total body Zn g-1 day"1 at 10 °C. The increased ability of P. elegans to regulate zinc in the presence of EDTA may be explained by the reduced bioavailability of the zinc-EDTA complex for uptake. There is marked individual variation in the rate of uptake of labelled zinc in prawns, even in the presence of the same concentration of zinc or zinc-EDTA.

Water content and water turnover in beef cattle

1968 ◽  
Vol 19 (1) ◽  
pp. 129
Author(s):  
PH Springell
Keyword(s):  
Water Content ◽  
Half Life ◽  
Turnover Rate ◽  
Tritiated Water ◽  
Body Water ◽  
The Body ◽  
Turnover Rates ◽  
Water Turnover ◽  
Poor Diet ◽  
The Mean

Twenty-four steers, comprising British (Hereford and Hereford x Shorthorn), Zebu (Africander), and Zebu cross (British x Brahman or Africander) breeds, were either maintained on pasture, or yarded and fed on diets of a low and a high nutritional value. Tritiated water was injected into the animals on five occasions at intervals of 3 months. The body water content and the water turnover rate were calculated, and some of the sources of variation defined. Observed differences in the water content are attributable to nutritional factors rather than to breed differences. The mean body water content ranged from 615 to 809 ml/kg fasting body weight, where the higher values were associated with a poor diet. The mean half-life of tritiated water was lower in summer (as low as 58 hr) than in winter (up to 128 hr) in grazing and well-fed yarded steers. On a poor diet, however, the half-life in yarded cattle remained high and almost constant throughout the year, dropping to below 100 hr on only a single occasion. Occasionally the half-life was breed dependent, but generally no significant differences between breeds could be found. While mean turnover rates of up to 7.1 ml kg-1 hr-1 were found in better-fed cattle in summer, the value in poorly fed animals was almost constant throughout the year at about 3.3 ml kg-1 hr-1. There was, however, a winter minimum in the well-fed yarded and grazing groups. The turnover rate was also influenced by breed only to a limited extent. The results are interpreted in the light of their possible significance in the adaptation to a tropical environment, and in relation to their value in predicting the body composition.

BODY WATER OF NEWBORN INFANTS OF DIABETIC MOTHERS

1960 ◽  
Vol XXXIV (II) ◽  
pp. 261-276 ◽  
Author(s):  
Mogens Osler
Keyword(s):  
Body Weight ◽  
Water Content ◽  
Total Body Water ◽  
Newborn Infants ◽  
Body Water ◽  
The Body ◽  
Intracellular Water ◽  
Extracellular Water ◽  
Total Body ◽  
Diabetic Mothers

ABSTRACT The total body water as well as the distribution of water in the extracellular and intracellular compartments was determined in 23 infants born to diabetic mothers (diab. infants) and 15 infants born to normal mothers (normal infants). The total body water was determined by the dilution method using heavy water, and the extracellular water by the dilution method using thiosulphate. Intracellular water was calculated as total water less extracellular water. The analytical methods are described. Diab. infants proved to have a mean total body water of 2.48 litres or 70.2 per cent of the body weight, a mean extracellular water content of 1.41 litre or 38.5 per cent of the body weight, and a mean intracellular water content of 1.16 litre or 31.8 per cent of the body weight. Normal infants had a mean total body water of 2.58 litres or 78.2 per cent of the body weight, a mean extracellular water content of 1.53 litre or 44.9 per cent of the body weight, and a mean intracellular water content of 1.12 litre or 33.5 per cent of the body weight. The reduction in total and extracellular water in the diab. infants is statistically significant, whereas that of intracellular water is more doubtful. The reduction in total body water means that diab. infants are obese. A marked decrease in total as well as extracellular water without a substantial decrease in intracellular water cannot be due to obesity alone, since fat is assumed to contain more extracellular than intracellular water. Increased deposition of glycogen, which binds water in the cells and constitutes an intermediate product in the transformation of glucose to fat, can explain, when also considering the obesity, the reduction in total and extracellular water without a simultaneous decrease of intracellular water. Considering the influence of insulin, corticosteroids and growth hormone on the body composition, the author concludes that the changes found in the body composition of newborn infants of diabetic mothers (obesity + presumably increased glycogen) may be assumed to be due to maternal hyperglycaemia with consequent foetal hyperglycaemia + hyperinsulinism, but not to an action of maternal growth hormone. In other words, the result supports the so-called hyperglycaemia hypothesis as the cause of the increased weight and changed body composition of the newborn infants of diabetic women.

scholarly journals Edelman Revisited: Concepts, Achievements, and Challenges

2022 ◽  
Vol 8 ◽  
Author(s):  
Mark Rohrscheib ◽  
Ramin Sam ◽  
Dominic S. Raj ◽  
Christos P. Argyropoulos ◽  
Mark L. Unruh ◽  
...  
Keyword(s):  
Serum Sodium ◽  
Quantitative Methods ◽  
Sodium Concentration ◽  
Body Fluids ◽  
Body Water ◽  
Serum Sodium Concentration ◽  
Sodium Potassium ◽  
Body Sodium ◽  
Total Body

The key message from the 1958 Edelman study states that combinations of external gains or losses of sodium, potassium and water leading to an increase of the fraction (total body sodium plus total body potassium) over total body water will raise the serum sodium concentration ([Na]S), while external gains or losses leading to a decrease in this fraction will lower [Na]S. A variety of studies have supported this concept and current quantitative methods for correcting dysnatremias, including formulas calculating the volume of saline needed for a change in [Na]S are based on it. Not accounting for external losses of sodium, potassium and water during treatment and faulty values for body water inserted in the formulas predicting the change in [Na]S affect the accuracy of these formulas. Newly described factors potentially affecting the change in [Na]S during treatment of dysnatremias include the following: (a) exchanges during development or correction of dysnatremias between osmotically inactive sodium stored in tissues and osmotically active sodium in solution in body fluids; (b) chemical binding of part of body water to macromolecules which would decrease the amount of body water available for osmotic exchanges; and (c) genetic influences on the determination of sodium concentration in body fluids. The effects of these newer developments on the methods of treatment of dysnatremias are not well-established and will need extensive studying. Currently, monitoring of serum sodium concentration remains a critical step during treatment of dysnatremias.

Body Fluid Spaces in Patients on CAPD

1984 ◽  
Vol 7 (2) ◽  
pp. 89-91 ◽  
Author(s):  
G. Panzetta ◽  
U. Guerra ◽  
A. D'angelo ◽  
S. Sandrini ◽  
A. Terzi ◽  
...  
Keyword(s):  
Body Weight ◽  
Distinctive Feature ◽  
Total Body Water ◽  
Body Fluid ◽  
Mean Value ◽  
Body Water ◽  
Extracellular Water ◽  
Intracellular Space ◽  
The Mean ◽  
Total Body

Total body water (TBW) and extracellular water (ECW) were determined in 9 CAPD patients on treatment from 5 to 14 months (mean 8.6 months). The mean value of TBW was normal and directly correlated to body weight, but TBW was abnormally distributed between extracellular and intracellular space. ECW volume was significantly lower than the predicted value (12.1 ± 1.4 I versus 16.8 ± 1.9 I) and out of proportion to TBW (34.8 ± 3.9% versus 47.8 ± 1.5%). The calculated ICW, therefore, appeared clearly hyperexpanded. The data suggest that cell overhydration was the distinctive feature in our CAPD patients.

EXAMINATION OF THE HYPOTHESIS OF A CRITICAL WEIGHT AT MENARCHE IN AMBULATORY AND BEDRIDDEN MENTALLY RETARDED GIRLS

PEDIATRICS ◽  
1973 ◽  
Vol 51 (4) ◽  
pp. 675-679 ◽  
Author(s):  
David C. Osler ◽  
John D. Crawford
Keyword(s):  
Water Content ◽  
Body Fat ◽  
Total Body Water ◽  
Mentally Retarded ◽  
Characteristic Parameter ◽  
Body Water ◽  
Age At Menarche ◽  
Critical Weight ◽  
The Mean ◽  
Total Body

The ages, weights, and calculated total body water and body fat contents as menarche of 44 mentally retarded, institutionalized girls were examined to determine whether they were in accord with the hypothesis that menarche is dependent upon achievement of a critical weight or body water content. The findings in the 35 ambulatory children were in accord with the hypothesis, menarche being achieved later but at attainment of the same weight and body water content as in normal girls. The mean age at menarche of the nine bedridden retarded children was slightly less than that of their ambulatory counterparts and their weights and calculated body water and fat contents were substantially below those of normal girls at menarche. It is suggested that the effect of being bedridden may be to lower the metabolic rate, thus hastening the time when it falls to the level of 28 calories/kg/24 hr, a characteristic parameter of normal girls at menarche.

Corrigendum - Water content and water turnover in beef cattle

1968 ◽  
Vol 19 (1) ◽  
pp. 129
Author(s):  
PH Springell
Keyword(s):  
Water Content ◽  
Half Life ◽  
Turnover Rate ◽  
Tritiated Water ◽  
Body Water ◽  
The Body ◽  
Turnover Rates ◽  
Water Turnover ◽  
Poor Diet ◽  
The Mean

Twenty-four steers, comprising British (Hereford and Hereford x Shorthorn), Zebu (Africander), and Zebu cross (British x Brahman or Africander) breeds, were either maintained on pasture, or yarded and fed on diets of a low and a high nutritional value. Tritiated water was injected into the animals on five occasions at intervals of 3 months. The body water content and the water turnover rate were calculated, and some of the sources of variation defined. Observed differences in the water content are attributable to nutritional factors rather than to breed differences. The mean body water content ranged from 615 to 809 ml/kg fasting body weight, where the higher values were associated with a poor diet. The mean half-life of tritiated water was lower in summer (as low as 58 hr) than in winter (up to 128 hr) in grazing and well-fed yarded steers. On a poor diet, however, the half-life in yarded cattle remained high and almost constant throughout the year, dropping to below 100 hr on only a single occasion. Occasionally the half-life was breed dependent, but generally no significant differences between breeds could be found. While mean turnover rates of up to 7.1 ml kg-1 hr-1 were found in better-fed cattle in summer, the value in poorly fed animals was almost constant throughout the year at about 3.3 ml kg-1 hr-1. There was, however, a winter minimum in the well-fed yarded and grazing groups. The turnover rate was also influenced by breed only to a limited extent. The results are interpreted in the light of their possible significance in the adaptation to a tropical environment, and in relation to their value in predicting the body composition.

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