Water Balance in Corixa Dentipes (Thoms.) (Hemiptera, Heteroptera)

1964 ◽  
Vol 41 (3) ◽  
pp. 609-619
Author(s):  
B. W. STADDON

1. The water balance in Corixa dentipes (Thoms.) has been investigated under conditions of starvation in de-ionized water. 2. The rectal fluid was found to contain almost sufficient ammonium bicarbonate to account for the total osmotic pressure. It was invariably strongly hypotonic to the haemolymph. 3. The water output, as estimated by measuring the ammonia output and ammonia concentration of the rectal fluid, was shown to be appreciable but no connexion was found between the output of ammonia and of water. 4. Adults were shown to gain water by the mouth and some evidence was obtained that the cuticle may be an important route of water intake.

1981 ◽  
Vol 96 (2) ◽  
pp. 493-496 ◽  
Author(s):  
A. A. Degen ◽  
B. A. Young

Environmental conditions (Clark & Quin, 1949; Daws & Squires, 1974; Degen & Young, 1980) and total feed intake (Clark & Quin, 1949; Forbes, 1968; Degen & Young, 1980) influence the water intake of sheep. In general, high temperatures increase the requirements for water needed for evaporative cooling and high feed intakes necessitate more water for excretion of waste products. This study was designed to measure water intake and estimate the partition of water output in sheep maintained at four air temperatures and offered four levels of a ration.


1996 ◽  
Vol 80 (6) ◽  
pp. 1968-1972 ◽  
Author(s):  
K. R. Westerterp ◽  
P. Robach ◽  
L. Wouters ◽  
J. P. Richalet

The present study is a first attempt to measure water balance and its components at altitude by using labeled water and bromide dilution and relating the results with acute mountain sickness (AMS). Water intake, total water output, and water output in urine and feces were measured over a 4-day interval before and a subsequent 4-day interval after transport to 4,350 m. Total body water and extracellular water were measured at the start and at the end of the two intervals. There was a close relationship between energy intake and water intake, and the relationship was unchanged by the altitude intervention. Subjects developing AMS reduced energy intake and water intake cor respondingly. The increase in total body water (TBW) in subjects developing AMS was accompanied by a reduction in total water loss. They did not show the increased urine output, compensating for the reduced evaporative water loss at altitude. Subjects showed a significant increase in TBW after 4 days at altitude. Subjects with AMS showed the biggest shifts in extracellular water relative to TBW. In conclusion, fluid retention in relation to AMS is independent of a change in water requirements due to altitude exposure. Subjects developing AMS were those showing a fluid shift of at least 1 liter from the intracellular to the extracellular compartment or from the extracellular to the intracellular compartment.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Alejandra Carretero-Krug ◽  
Natalia Úbeda ◽  
Carlos Velasco ◽  
Juan Medina-Font ◽  
Trinidad Trujillo Laguna ◽  
...  

Abstract Background An adequate hydration status is critical to ensure efficiency during mental and physical activities. Our goal was to assess the hydration status of a Spanish group of aeronautical military men and to determine the association of hydration status with body composition and anxiety. Methods A total of 188 men were evaluated through a validated hydration questionnaire, anthropometric and biochemical parameters, and an anxiety questionnaire. Based on these methods, the criteria of hydration were established. Results Of the total sample, 81% met the hydration criteria (urine color = well hydrated, water balance ≥ 0 ml, and total water intake/weight ≥ 35 ml/kg), and 19% did not meet the hydration criteria (urine color = not sufficiently hydrated or dehydrated, water balance < 0 ml, and total water intake/weight < 35 ml/kg). Subjects not meeting the hydration criteria had lower urine pH, negative water balance, and lower water intake. The latter also had higher anxiety status (score = 4 vs. 3, P = 0.026), weight [(84.7 ± 10.5) vs. (80.5 ± 10.2) kg], body mass index [(26.3 ± 3.1) vs. (25.2 ± 2.8)]kg/m2, body fat [(22.3 ± 5.6) vs. (18.3 ± 6.5)] %, urine specific gravity, and urine color. Using a logistic binary regression model, hydration status was related significantly with the percentage of body fat (P = 0.004), but no relation was found with age, comorbidities, or medications. Furthermore, total water intake/weight was positively correlated with percentage of body water (r = 0.357, P = 0.000) and negatively with body fat (kg) (r = − 0.427, P = 0.000), percentage of body fat (r = − 0.405, P = 0.000), and waist/hip ratio (r = − 0.223, P = 0.002). Based on a linear regression model, total water intake/weight was related significantly with percentage of body fat (P = 0.001) and percentage of body water content (P = 0.035). No relation was found, however, with waist/hip ratio, age, comorbidities, or medications. Conclusions These findings all suggest a relationship between hydration status and body composition but also set the bases for future studies that relate hydration status and anxiety status. These results can be used to improve the hydration status and body composition of military personnel.


2017 ◽  
Author(s):  
Richard H Sterns ◽  
Stephen M. Silver ◽  
John K. Hix ◽  
Jonathan W. Bress

Guided by the hypothalamic antidiuretic hormone vasopressin, the kidney’s ability to conserve electrolyte–free water when it is needed and to excrete large volumes of water when there is too much of it normally prevents the serum sodium concentration from straying outside its normal range. The serum sodium concentration determines plasma tonicity and affects cell volume: a low concentration makes cells swell, and a high concentration makes them shrink. An extremely large water intake, impaired water excretion, or both can cause hyponatremia. A combination of too little water intake with too much salt, impaired water conservation, or excess extrarenal water losses will result in hypernatremia. Because sodium does not readily cross the blood-brain barrier, an abnormal serum sodium concentration alters brain water content and composition and can cause serious neurologic complications. Because bone is a reservoir for much of the body’s sodium, prolonged hyponatremia can also result in severe osteoporosis and fractures. An understanding of the physiologic mechanisms that control water balance will help the clinician determine the cause of impaired water conservation or excretion; it will also guide appropriate therapy that can avoid the life-threatening consequences of hyponatremia and hypernatremia.


1960 ◽  
Vol 199 (2) ◽  
pp. 238-242 ◽  
Author(s):  
J. S. Lee ◽  
Nathan Lifson

A test has been carried out in rats of the possibility of measuring with the aid of doubly labeled water (D2O18) the following components of the material balance of an animal: output of CO2 and water; intake of oxygen, food and water. The items of information used for the measurement were a) isotopic analyses of initial and final blood samples, b) composition of the diet with respect to percentage protein, carbohydrate and fat, c) initial and final body weight, d) final percentage body water. Initial percentage body water obtained from a by the volume of dilution principle could substitute for d. CO2 and water output were estimated isotopically; O2 consumption, from the CO2 output and dietary R. Q.; food intake, from CO2 output and dietary composition; water intake, from the difference between water output and dietary metabolic water. A rough correction for storage of materials was made from the change in body weight. The average difference between observed values for each of the above components of the material balance and values calculated by the isotope procedure was less than 10%. The fact that dry air was supplied to the animal in the metabolism chamber used to obtain the observed values probably favored better agreement between calculated and observed values for water intake and output than would prevail in ordinary moist air.


2000 ◽  
Vol 279 (6) ◽  
pp. F1014-F1026 ◽  
Author(s):  
Dominique Promeneur ◽  
Tae-Hwan Kwon ◽  
Masato Yasui ◽  
Gheun-Ho Kim ◽  
Jørgen Frøkiær ◽  
...  

In the rat, aquaporin-6 (AQP6) is mainly localized in intercalated cells (ICs) in collecting ducts, where it is exclusively associated with intracellular vesicles. In this study, we examined whether AQP6 protein and mRNA expression were regulated in the inner medulla or inner stripe of the outer medulla. Rats treated with dietary alkali or acid load for 7 days with a fixed daily water intake revealed appropriate changes in urine pH but unchanged urine output. AQP6 protein and mRNA abundance were increased in alkali-loaded rats (187 ± 18 and 151 ± 17% of control, respectively), whereas no changes were observed in acid-loaded rats. Immunohistochemistry revealed increased IC AQP6 labeling in alkali-loaded rats but not in acid-loaded rats. In contrast, administration of NH4Cl in the drinking water for 2 wk (free access to water) revealed a significant increase in AQP6 protein abundance (194 ± 9% of control), but this was associated with increased water intake. Combined, this suggests that AQP6 expression was not affected by acid loading per se but rather was in response to changes in water intake. Consistent with this, water loading for 48 h was associated with increased AQP6 protein abundance, compared with thirsted rats. Moreover, rats with lithium-induced nephrogenic diabetes insipidus had a threefold increase in both AQP6 protein and mRNA expression. Overall, these results suggest that AQP6 expression in collecting duct ICs is regulated by altered acid/alkali load or water balance. Thus AQP6 may contribute to maintenance of acid-base homeostasis and water balance.


1976 ◽  
Vol 24 (1) ◽  
pp. 7 ◽  
Author(s):  
PR Baverstock

While Rattus fuscipes survived only 4 days of water deprivation at 21�C, R. norvegicus, R. villosissimus and R. lutreolus survived 13-16 days. There was considerable inter-individual variation in the response of water-deprived R. villosissimus. Analysis of osmotic pressure, urea, sodium, potassium and chloride of both plasma and urine of rats with and without drinking water revealed that: (1) the abilities of R. norvegicus and R. villosissimus to tolerate water deprivation were due in large part to their abilities to produce highly concentrated urine; (2) R. lutreolus tolerated long periods of water deprivation not by urine-concentrating ability but by partly abandoning homeostasis and tolerating elevated levels of plasma solutes; (3) water-deprived R. fuscipes excreted large volumes of concentrated urine, possibly because their relatively high metabolic rate necessitated the excretion of excess metabolites. In all of the rats, urea constituted an unusually low proportion of the total osmotic pressure. The water-balance response of water-deprived rats is at variance with both their macrogeographical distribution and microhabitat preferences.


1963 ◽  
Vol 204 (5) ◽  
pp. 817-820 ◽  
Author(s):  
H. Schmidt ◽  
L. Dry

The effect of phenobarbital, amobarbital, and secobarbital upon the volume of water ingested by thirsty rats was investigated shortly after injection, 1 day later, and 2 days later. The first effect was the characteristic rise in water intake at low dosages, and a fall at higher dosages. Twenty-four hours later there is a fall at the lower dosages, and a rise at the higher quantities. Two days after injection, there was some quite slight residual effect of both amobarbital and secobarbital but equilibration was nearly complete. Phenobarbital demonstrates some depressant activity at this time. When phenobarbital is administered and water ingestion held at a constant level for 2 days, the depressant effect is still obtained. These data indicate that the barbiturates have sequential effects upon water ingestion which are to some large degree independent of water balance per se.


2013 ◽  
Vol 26 ◽  
pp. 90-96 ◽  
Author(s):  
O. Malisova ◽  
V. Bountziouka ◽  
D. Β. Panagiotakos ◽  
A. Zampelas ◽  
M. Kapsokefalou

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