Sodium Regulation in the Crayfish Astacus Fluviatilis

1960 ◽  
Vol 37 (1) ◽  
pp. 83-99 ◽  
Author(s):  
G. W. BRYAN

1. In Bristol tap water containing 0.4 mM./l. sodium and artificial tap water containing 2 mM./l. sodium, Astacus maintains a blood sodium concentration of about 203 mM./l. This value was not markedly affected by starvation periods of up to a month. 2. Methods of taking small blood and urine samples from individual crayfish at intervals over several hundred hours have been described. 3. Under steady state conditions, curves for the uptake and loss of 22Na by the blood are described by equations derived for a one-compartment system. 4. The volume of this single compartment, which exchanges sodium with the medium, is larger than the actual blood volume by an amount roughly equivalent to the sodium in the tissues. Exchange of sodium between the blood and tissues is probably very rapid. 5. Sodium losses in the urine account for about 6% of the total sodium outflux found using 22Na. The urine sodium concentration of about 6 mM./l. was temporarily increased by conditions such as heavy feeding when the blood may have gained additional sodium. 6. Potential difference measurements across the body surface indicate that the high blood sodium concentration is maintained by active uptake of sodium.

1960 ◽  
Vol 37 (1) ◽  
pp. 113-128
Author(s):  
G. W. BRYAN

1. In external sodium concentrations of up to 100 mM./l. the blood sodium concentration of Astacus is only slightly increased. As the external level approaches or exceeds the normal blood sodium concentration of 200 mM./l. so the increase becomes more marked. Similarly, there is an increase in urine sodium concentration. This net gain of sodium is accompanied by a considerable rise in sodium outflux as shown by 22Na. At external concentrations exceeding 300 mM./l., blood and urine concentrations rise to a similar level and active sodium movements appear to cease. 2. With increased blood sodium concentration the level in the muscles rises also. This relationship is not one of simple proportion and at high concentrations there is relatively more sodium in the muscles. 3. In artificial tap water animals with a high blood concentration lose sodium until the normal level is regained. This net loss is due to influx being much lower and outflux much higher than normal. Of the outflux, up to 70% is initially due to renal losses and losses over the body surface are higher than normal due to the excess sodium in the blood. 4. From the results given in this and previous papers the way in which sodium balance may be achieved under normal conditions is discussed.


1960 ◽  
Vol 37 (1) ◽  
pp. 100-112
Author(s):  
G. W. BRYAN

1. In distilled water or artificial tap water with a very low sodium concentration, sodium uptake by Astacus is prevented or reduced and 22Na outflux is subnormal. This is accounted for to only a small extent by reduced renal sodium losses. 2. Sodium-depleted animals replaced in artificial tap water regain sodium in a roughly exponential manner. This is shown by 22Na to be the result of a considerable increase in sodium influx coupled with an increased but lower outflux. 3. Sodium outfiux appears to consist of three components: urine losses, passive diffusion losses over the body surface and what may be an ‘exchange diffusion’ component which is high during high influx and minimal in distilled water. This latter component represents about 30% of sodium exchange under normal conditions. 4. Eyestalk removal did not affect the ability of Astacus to absorb sodium. 5. In starved animals the gills take up most of the sodium absorbed and the gut is relatively unimportant. 6. Silver staining of the gills is a passive process and the cuticle of the branchial filaments of the gill stem is selectively stained. This region would be a suitable site for ion uptake mechanisms.


1970 ◽  
Vol 53 (1) ◽  
pp. 147-163 ◽  
Author(s):  
PETER GREENAWAY

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.


1968 ◽  
Vol 48 (2) ◽  
pp. 359-380
Author(s):  
D. W. SUTCLIFFE

1. Sodium uptake and loss rates are given for three gammarids acclimatized to media ranging from fresh water to undiluted sea water. 2. In Gammarus zaddachi and G. tigrinus the sodium transporting system at the body surface is half-saturated at an external concentration of about 1 mM/l. and fully saturated at about 10 mM/l. sodium. In Marinogammarus finmarchicus the respective concentrations are six to ten times higher. 3. M. finmarchicus is more permeable to water and salts than G. zaddachi and G. tigrinus. Estimated urine flow rates were equivalent to 6.5% body weight/hr./ osmole gradient at 10°C. in M. finmarchicus and 2.8% body weight/hr./osmole gradient in G. zaddachi. The permeability of the body surface to outward diffusion of sodium was four times higher in M. finmarchicus, but sodium losses across the body surface represent at least 50% of the total losses in both M. finmarchicus and G. zaddachi. 4. Calculations suggest that G. zaddachi produces urine slightly hypotonic to the blood when acclimatized to the range 20% down to 2% sea water. In fresh water the urine sodium concentration is reduced to a very low level. 5. The process of adaptation to fresh water in gammarid crustaceans is illustrated with reference to a series of species from marine, brackish and freshwater habitats.


1967 ◽  
Vol 46 (3) ◽  
pp. 499-518
Author(s):  
D. W. SUTCLIFFE

1. Sodium influx and loss rates in Gammarus pulex were measured at constant temperatures. The sodium loss rate was immediately influenced by a change in temperature, with a Q10 of 1.5 to 2.0 at temperatures between 0.3 and 21.5° C. The sodium influx rate is apparently influenced in the same way. 2. The sodium uptake mechanism in G. pulex from three localities was half-saturated at an external concentration of 0.10-0.15 mM/l. sodium. 3. The total sodium loss rate remained approximately constant in animals acclimatized to the range of external concentrations from 2 to about 0.2 mM/l. sodium. 18% of the sodium was lost in urine with a sodium concentration estimated at 30-50 mM/l. The remainder of the sodium loss was due to diffusion across the body surface. 4. In animals acclimatized to concentrations below about 0.2 mM/l. sodium the sodium loss rate was reduced, due to (a) a lower diffusion rate following a fall in the blood sodium concentration, and (b) the elaboration of a more dilute urine. 5. There was a very close association between changes in the blood sodium concentration, the elaboration of a very dilute urine, and the rate of sodium uptake at the body surface. The results indicate that a fall in the blood sodium concentration leads to simultaneous activation of the sodium uptake mechanisms at the body surface and in the antennary glands. 6. It is estimated that, by producing a dilute urine, total sodium uptake in G. pulex is shared equally between the renal uptake mechanism and the mechanism situated at the body surface. 7. In sea-water media G. pulex drinks and expels fluid from the gut. In a medium slightly hyperosmotic to the normal blood concentration the amount imbibed was equal to the normal rate of urine flow when in fresh water.


1960 ◽  
Vol XXXIII (IV) ◽  
pp. 630-636
Author(s):  
F.-E. Krusius ◽  
P. Peltola

ABSTRACT The study reported here was performed in order to examine the tap water of Helsinki for its alleged goitrogenous effect. In a short-term, 24-hour experiment with rats, kept on an iodine-poor diet, we noticed no inhibition of the 4-hour 131I uptake, as compared with that of animals receiving physiological saline instead of tap water. Two similar groups of rats receiving 1 and 2 mg of mercazole in redistilled water showed a distinct blockage of the 4-hour uptake, which proved the effect of this substance. In a long-term experiment of 5 weeks' duration there was no detectable difference in the body weight, thyroid weight and the 4-hour 131I uptake when the rats receiving tap water or distilled water to which 0.45 per cent of sodium chloride was added were compared with each other. Replacement of tap water by a 10 mg per cent solution of mercazole in redistilled water enlarged the thyroid to double its normal weight and increased the 131I uptake to approximately five times that of the controls. Thus our experiments failed to demonstrate any goitrogenous effect in the tap water of Helsinki. Changes similar to those produced by a long-term administration of mercazole, i. e. an enlargement of the thyroid and an increased thyroidal iodine uptake, have been shown to be due to milk collected from goitrous areas. The observations here reported confirm the importance of milk in the genesis of the goitre endemia of Helsinki. Attention is further called to the fact that a thyroidal enlargement combined with an increased thyroidal iodine uptake cannot always be taken as a sign of iodine deficiency because similar changes may be produced by the administration of goitrogens.


Author(s):  
Beschasnyi S.P. ◽  
Lysenko E.M. ◽  
Hasiuk O.M. ◽  
Erlish О.О.

Carbon monoxide is a toxic gas that is colourless, odourless, and has the potential to cause momentaryhypoxia by bonding with heme-inspired proteins. Because of these properties, it causes the highest number of toxications. Due to its properties, this gas causes damage to the nervous and cardiovascular system. The development of anoxia is associated with the impact on the system of oxidative phosphorylation in mitochondria and the development of oxidative stress in the body. The body produces a small amount of carbon monoxide as a result of erythrocyte breakdown. Picomolar concentrations of carbon monoxide even have anti-inflammatory, antiapoptotic,cytoprotective and antiproliferative properties. Kidney is one of the first organs,that responds to the occurrence of hypoxia, are responsible for the removal of products of metabolism and toxicants, including ethanol. For the study, the blood and urine samples were taken from patients with acute intoxication. The amount of methemoglobin in the blood was determined by spectrophotometric method. The concentration of ethanol in blood and urine was measured by gas-liquid chromatography method. The correlation analysis showed that carbon monoxide affects the rate of excretion of ethanol from the body. Among individuals under 40 years of age, there was a correlation between the level of carbon monoxide and the amount of ethanol in the blood. Among older adults this correlation was not established. A direct correlation with the level of this gas in the blood and the level of ethanol in the urine among people under 40 years of age was found. Among older individuals, the opposite was observed –a high level of methemoglobin was responsible for the decreased level of ethanol. There were no correlations between methemoglobin level and age. Comparison of the studied indices did not show any sexual differences in ethanol excretion, but there were age specific features: ethanol excretion under the influence of carbon monoxide among people under 40 years old was more accelerated.Key words:hypoxia, CO intoxication, blood, methemoglobin, kidneys. Монооксид карбону являє собою токсичний газ, який не має кольору,без запаху та здатен спричиняти миттєву гіпоксію шляхом зв’язування з гем-вмісними білками. Через такі властивості він спричиняє найбільшу кількість отруєнь. Цей газ,завдяки своїм властивостям,спричиняє ураження нервової та серцево-судинної системи. Розвиток аноксії пов’язаний із впливом на систему окисного фосфорилювання у мітохондріях та розвиткомоксидативного стресу. В організмі продукується невелика кількість ендогенного монооксиду карбону внаслідок розпаду еритроцитів. Пікомолярні концентрації монооксиду карбону навіть володіють протизапальними, антиапоптичними, цитопротекторними та антипроліферативними властивостями. Нирки є одним із перших органів, який реагує на розвитокгіпоксії, вони відповідають за видалення продуктів метаболізму й токсикантів, зокрема етанолу.Зміни у функціонуванні нирок відображаються на загальному стані організму.Для дослідження отримували зразки крові та сечі від осіб із гострою інтоксикацією. У крові спектрофотометричним методом визначали вміст метгемоглобіну, який утворювався внаслідок вдихання монооксиду карбону та відповідного потрапляння до кровоносної системи. Методом газово-рідинної хроматографії вимірювали концентрацію етанолу у крові та сечі. Розрахунок кореляційних зв’язків показав, що монооксид карбону впливає на швидкість екскреції етанолу. У осіб до 40 років спостерігалася кореляція між показником рівня метгемоглобінута вмістом етанолу у крові. У осіб старшого віку цього зв’язку не встановлено. Виявлено прямий зв’язок із рівнем цього газу у крові та рівнем етанолу в сечі у осіб до 40 років. У осіб старшого віку спостерігалася зворотня реакція–високий рівень метгемоглобінуобумовлював зниження рівня етанолу. Кореляційні зв’язки між вмістом метгемоглобіну та віком не було виявлено. Порівняння досліджуваних показників не виявило статевих відмінностей у екскреції етанолу, проте виявлено вікові особливості: екскреція етанолу в умовах впливу монооксиду карбону в осіб до 40 років була більш пришвидшена.Таким чином, можна стверджувати, що монооксид карбону обумовлює зміни у функціональній активності нирок.Ключові слова:гіпоксія, інтоксикація СО, кров, метгемоглобін, нирки.


2012 ◽  
Vol 7 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Anita M. Rivera-Brown ◽  
Roberto A. De Félix-Dávila

Adolescent judo athletes who train in tropical climates may be in a persistent state of dehydration because they frequently restrict fluids during daily training sessions to maintain or reduce their body weight and are not given enough opportunities to drink.Purpose:Determine the body hydration status of adolescent judo athletes before, immediately after, and 24 h after (24H) a training session and document sweat Na+ loss and symptoms of dehydration.Methods:Body mass and urine color and specific gravity (USG) were measured before, after, and 24 h after a training session in a high-heat-stress environment (29.5 ± 1.0°C; 77.7 ± 6.1% RH) in 24 adolescent athletes. Sweat sodium loss was also determined. A comparison was made between mid-pubertal (MP) and late pubertal (LP) subjects.Results:The majority of the subjects started training with a significant level of dehydration. During the training session, MP subjects lost 1.3 ± 0.8% of their pretraining body mass whereas LP subjects lost 1.9 ± 0.5% (P < .05). Sweat sodium concentration was 44.5 ± 23.3 mmol/L. Fluid intake from a water fountain was minimal. Subjects reported symptoms of dehydration during the session, which in some cases persisted throughout the night and the next day. The 24H USG was 1.028 ± 0.004 and 1.027 ± 0.005 g/mL for MP and LP, respectively.Conclusions:Adolescent judo athletes arrive to practice with a fluid deficit, do not drink enough during training, and experience symptoms of dehydration, which may compromise the quality of training and general well-being.


1956 ◽  
Vol 33 (1) ◽  
pp. 29-44 ◽  
Author(s):  
BETTY I. ROOTS

1. The water content of Lumbricus terrestris, after keeping on moist filter-paper for 3 or 4 days, is 84.8% of its body weight. That of Allolobophora chlorotica is 80% of its body weight. Both species can survive a loss of 60% of the body weight, but not much more. 2. Earthworms of the species A. chlorotica, A. terrestris f. longa, Dendrobaena subrubicunda, L. rubellus and L. terrestris are all able to survive from 31 to 50 weeks in soil totally submerged beneath aerated water. The same species, and A. caliginosa can survive for 72-137 days in aerated tap water without food. 3. Garden specimens of A. chlorotica make U-shaped burrows in soil beneath water. They do not irrigate either the burrows or glass tubes. Egg-cocoons of A. chlorotica, taken from culture pots of soil, will hatch under water and the young worms will feed and grow though totally immersed.


Author(s):  
Senthilnathan Prof.Dr.C.V. ◽  
Vaishnavi G. ◽  
Keerthana G. ◽  
NandhaKumar S. ◽  
Kotteeswaran Prof.Dr.

Hyperhidrosis is an excessive production of sweat more than the physiological amount necessary to maintain thermal homeostasis. Primary focal hyperhidrosis is a disorder of unknown etiology, causing excessive, bilateral, symmetrical sweating on the soles of the foot is called plantar hyperhidrosis. The condition results not only in physical impairment, but also interferes with professional and social life. Although not life-threatening, it is very uncomfortable and cause embarrassment and psychological trauma. Iontophoresis is a helpful method, which includes the presentation of particles into the body tissue through the skin. The essential principle is to place the ion particles under an electrode with the same charge, i.e. negative ion placed under cathode and positive ion placed under anode. This complete process is also known as “technique of ion transfer” into the body tissues by using electrical current as a driving force. It is a comparative study with pre and post intervention. 30 subjects with plantar hyperhidrosis were selected based on the inclusion criteria. The study duration was for about 4 weeks30 subjects of age group between 15 – 25 years with idiopathic plantar hyperhidrosis of both male and female subjects were included in this study. Subjects with cardiac and respiratory disorders, pregnant or lactating, any cuts, abrasions, eczema or infections on plantar aspect, metal implants like pacemakers, Hypersensitivity to the active substance were excluded. The subjects were divided into 3 group Group A treated with iontophoresis using tap water alone. Group B were treated with iontophoresis using tap water along with 3%-5% of anticholinergic drug, glycopyrronium bromide solution. Group C were treated with iontophoresis using tap water along with 1% of indomethacin (NSAID). The result of this study shows that there were significant changes in outcome measures. On comparing Mean values of Group A, Group B & Group C on Minor test (Starch - Iodine Test) tap Water along with Glycopyrronium Bromide (Group B) shows 1.60 which has the Lower Mean value is effective than Group A and Group C .On comparing Mean values of Group A, Group B & Group C on Visual Analog Scale score tap Water along with Glycopyrronium Bromide (Group B) shows 3.80 which has the Lower Mean value is effective than Group A and Group C. On comparing Mean values of Group A, Group B & Group C on Hyperhidrosis Disease Severity Scale tap Water along with Glycopyrronium Bromide (Group B) shows 1.40 which has the Lower Mean value is effective than Group A and Group C. On comparing all the three groups, Group B shows better result than Group C and Group A in outcome measure. This study concluded that Tap water along with glycopyrronium bromide reduces the excessive sweating and decrease the sweating symptoms in subjects with plantar hyperhidrosis.


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