Salt Exchange Research Articles

Renal adaptations by Opsanus tau, a euryhaline aglomerular teleost, to dilute media.

Renal adaptations by Opsanus tau, a euryhaline aglomerular teleost, to dilute media.

Friedel–Crafts rearrangements. III. Deuterium tracer studies of the mechanism of cyclialkylation of phenylalkyl chlorides

A series of dideuterated primary phenylalkyl chlorides 1-chloro-3-phenylpropane-2,2-d2 (4), 1-chloro-3-phenylpropane-1,1-d2 (9), 1-chloro-4-phenylbutane-2,2-d2 (8), 1-chloro-5-phenylpentane-4,4-d2 (5), 1-chloro-5-phenylpentane-3,3-d2 (6), and 1-chloro-5-phenylpentane-2,2-d2 (7) were synthesized by alkylations of malonic ester with phenylalkyl chlorides. Deuterium was introduced by exchange of the sodium salt of the alkylated malonic ester with D2O, followed by hydrolysis and decarboxylation. The resulting acids were reduced by hydride to primary alcohols and these were converted to the dideuterated primary chlorides by decomposition of the intermediate chlorosulfite esters. Nuclear magnetic resonance (n.m.r.) spectra confirmed the position of the deuterium in the chlorides. Friedel–Crafts cyclialkylation of the deuterated phenylpentyl chlorides yielded labelled 1-methyltetralins in which the label was located by n.m.r. and mass spectroscopy. The results demonstrated that rearrangement precedes cyclialkylation of 1-chloro-5-phenylpentane. Extensive deuterium scrambling between C-1, C-2, and C-3 accompanied the cyclialkylation of 5 but not that of 8. Reaction mechanisms are suggested to account for these results.

Multi-spot paper chromatograms of sodium orthophosphate

The formation of two zones on paper chromatograms was investigated by chromatographing orthophosphoric acid and the primary, secondary and tertiary sodium salts, using pyridine-ethyl acetate/water as mobile phase. Movement of the species from the origin depends on washing the paper with acid and suggests an exchange of protons for sodium as a prerequisite condition. Washing with EDTA does not alter this requirement. Zone movement and multi-spot formation require that the forming solvent contain at least 5% of water (v/v). Between this value and saturation, increasing water content enhances zone disengagement. A solute spot of a sodium salt exchanges with the protons to produce a fast-migrating protonated phosphate species. If the solute sample has a sodium content less than the amount of exchangeable protons, a single fast spot is produced ; if the concentration exceeds this capacity, a second slower spot results.

THE MECHANISM OF LONGITUDINAL DIFFUSION IN A TIDAL RIVER

Abstract The intrusion of seawater in a tidal river is treated as a diffusion problem, characterized by a coefficient of longitudinal diffusivity. In order to analyse the longitudinal diffusivity, a mathematical model is set up, consisting of two bodies of water, either one besides the other or one on top of the other. The two bodies are assumed to move relatively to each other, as a secondary effect of the tidal flow. It is moreover assumed that there is turbulent exchange of salt between the bodies. It is demonstrated that the diffusion of salt into the river is greatest for an optimum value of the coefficient of exchange between the two bodies. Exchange weaker or stronger than this optimum both diminish the salt intrusion. The theory is applied to the Rotterdam Waterway, for which estimates of the exchange are made. Estimation of the reduction of the turbulence by stratification and hence of the vertical exchange, shows that the observed strong intrusion is explainable. Intensified vertical mixing, for instance as provoked by compressed air, need not always result in less intrusion, and hence should be considered carefully.

Bacterial effect and radiophosphorus assimilation in organic and inorganic forms in salmon.

APPROXIMATELY 90 per cent of phosphorus present in the body of a fish is found in the skeleton. The remaining 10 per cent is chiefly intracellular and plays a major part in energy-transfer mechanisms. The reservoir of phosphorus in the skeleton is also of great importance in maintaining adequate levels of this element in the tissues. Fish selectively absorb inorganic salts from water, and concentrate in various tissues the elements of which these salts are composed1,2. Furthermore, freshwater fish do not swallow water nor absorb salts through their skin but they carry on salt exchange only across the gills3,4. The present work was taken up to study the effect of bacteria and radiophosphorus assimilation in organic and inorganic forms in salmon, Salmo salar L.

Salt balance and exchange rate for Chincoteague Bay

Salt balance and exchange rate for Chincoteague Bay

Stages of salt exchange in essential hypertension.

The relation of sodium to hypertension remains one of the most fascinating problems in medicine. The results accumulated over a five-year period of study of this relationship are presented in the paper which follows. In these investigations the appetite for salt and the output of sodium under a variety of loading conditions have been correlated with cardiac and renal function and compared with the patterns found in experimental corticoid and renal hypertensions.

A Linear Recording AC Conductance Bridge for Measuring Salt Exchange in Plants

Physiologia PlantarumVolume 6, Issue 3 p. 444-450 A Linear Recording AC Conductance Bridge for Measuring Salt Exchange in Plants Robert B. Withrow, Robert B. Withrow Division of Radiation and Organisms, Astrophysical Observatory, Smithsonian, Institution, Washington, D. C.Search for more papers by this authorAlice P. Withrow, Alice P. Withrow Division of Radiation and Organisms, Astrophysical Observatory, Smithsonian, Institution, Washington, D. C.Search for more papers by this author Robert B. Withrow, Robert B. Withrow Division of Radiation and Organisms, Astrophysical Observatory, Smithsonian, Institution, Washington, D. C.Search for more papers by this authorAlice P. Withrow, Alice P. Withrow Division of Radiation and Organisms, Astrophysical Observatory, Smithsonian, Institution, Washington, D. C.Search for more papers by this author First published: July 1953 https://doi.org/10.1111/j.1399-3054.1953.tb08402.xCitations: 2AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume6, Issue3July 1953Pages 444-450 RelatedInformation

Water and Salt Exchange During Chronic and Acute Dehydration in the Dog

Water and Salt Exchange During Chronic and Acute Dehydration in the Dog

A HIGH FLUID INTAKE IN THE MANAGEMENT OF EDEMA, ESPECIALLY CARDIAC EDEMA. II. CLINICAL OBSERVATIONS AND DATA

Excerpt It is only in the last 50 years that the limitation of fluids in the presence of edema has been taught and practiced so universally. Earlier clinicians noted that the theoretical fear of wa...

Regulation of the Haemolymph in the Saline Water Mosquito Larva Aedes Detritus Edw

ABSTRACT The larvae of the mosquito Aedes detritus have been reported only from definitely saline waters. They have been found in water of salinity equivalent to c. 10 % NaCl. In the laboratory they were acclimatized with ease to distilled water, sea water (7 % NaCl), 3 ·5 % NaCl, and glycerol (3 ·5 % NaCl). They also show considerable resistance to N/20 NaOH, but less to N/20 KOH and N/50 HC1. They are unable to live permanently in solutions of the chlorides of potassium, calcium and magnesium of osmotic pressure equivalent to 3 ·5 % NaCl. In sea water of varying salinity they can regulate both the total osmotic pressure and chloride content of the haemolymph. A rise from nil to 6 ·0 % NaCl in the osmotic pressure of the medium is reflected in an increase of from c. 0 ·8 % to 1 ·4% NaCl in that of the haemolymph. In hypotonic solutions and distilled water much chloride is lost, but this is compensated by an increase in the non-chloride fraction. In hypertonic sea water the rise in osmotic pressure is due to increase in the chloride fraction, the nonchloride fraction remaining constant. From this and from experiments with non-electrolytes it is concluded that the larva is permeable to salts and to molecules as large as glycerol, and that the regulatory mechanism in hypertonic saline is concerned with compensation rather for penetration of salts than for loss of water by osmosis. Ligature experiments suggest that this mechanism is the excretion of salt by the Malpighian tubes, but further proof is required. Salt exchange with the environment takes place via the gut, the body surface being impermeable to salts and water. The larvae are able to concentrate chloride from hypotonic solutions but not as effectively as fresh-water species and only when the chloride content of the medium is a little below that of the haemolymph. The anal gills, as in all salt-water species, are very small and appear to be impermeable to salts and water. It is therefore concluded that they are not the seat of the chloride-absorbing mechanism. The osmotic pressure of the haemolymph is trebled by treatment with glycerol (3 ·5 % NaCl), which must be mainly the result of penetration of glycerol. The larva will however live normally in this, and an important factor in the resistance to abnormal media is therefore the adaptability of the tissues to changes in the concentration and composition of the haemolymph. The increase in the osmotic pressure of the haemolymph induced by hypertonic sea water and glycerol does not alter the amount of fluid in the tracheoles. This is discussed in relation to the possible mechanism for the absorption of the trecheóle fluid.

Prof. August Krogh

THE election of Prof. A. Krogh to the Royal Society will give much pleasure to his many friends, who have been following with great admiration his remarkable achievements in different branches of physiology. His early work (1904) in collaboration with Bohr and Hasselbach demonstrated for the first time the effect of carbon dioxide on the affinity of hemoglobin for oxygen. In 1910 Krogh definitely proved that the absorption of oxygen and the elimination of carbon dioxide in the lungs take place by diffusion only and without the assistance of any secretory activity by the cells. This investigation finally settled the long-standing controversy around this problem. We owe to Krogh a series of important contributions to the study of the respiration of insects and the elaboration of a delicate technique for the accurate analysis of minute bubbles of gas. This technique was applied ultimately to the study of problems in other fields of physiology. Krogh's remarkable work on the capillary circulation, which was soon recognized by the award of the Nobel Prize in Physiology and Medicine, is marked by the same insistence on direct proof, combined with a broad biological outlook. The work of Krogh's laboratory to-day is largely concerned with the problems of respiration, especially at high altitudes, problems of circulation, the mechanism regulating the water and salt exchanges in aquatic animals, and the ecology of aquatic organisms in relation to the nitrogen cycle in water.

Respiration as a factor in the ionic equilibria between plant tissues and external solutions

Many investigations have been made of the salt exchange between slices of plant storage organs and solutions in which they have been placed. A simple form of experimentation is to place the pieces of tissue in water devoid of solutes, and to investigate the drift with time of the concentration of the external solution. The concentration of such a solution was used by Stiles and Kidd (1919) as a base line from which to calculate the absorption of salts by the tissue when placed in a salt solution. For example, the conductance of distilled water rose by 190 units in 52 hours when carrot tissue was placed in it, whereas that of 0·0002 N KCI increased only 137 units, whence it was deduced that the carrot tissue had absorbed KCI to the extent of 53 units of conductance. The justification for this procedure is doubtful, since a solution with which the tissue was in equilibrium would show no change of conductivity, and yet by this method of reasoning would be said to have lost salt to the extent of 190 units of conductance. More recently stiles (1927) has made detailed studies of the problem of the exosmosis of substances from slices of various storage tissues, including carrot root, into distilled water. Well-washed discs of tissue were placed in water and shaken continuously at 20° C. The drift of the conductance of the outside solution was followed. It rose for about 24 hours and then fell slowly for about 10 days, after which a steady value was maintained for some time until the conductance rose as the tissue died. The concentration of the outside solution was also determined by the weight of the residue after evaporating the solution to dryness. The concentration so determined followed the same course as the conductance. Stiles suggests that the initial liberation of electrolytes, which is greater the shorter the preliminary washing, takes place from the cut surface-cells and from the veils underneath, which soon die. These electrolytes are absorbed by the remaining living cells at a rate which is eventually greater than that at which they are liberated, with a consequent tail of the external conductivity. The tissue, small in bulk relative to the solution, would have to absorb the greater part of the electrolytes liberated. There is no direct evidence in favour of such an explanation. As far as we know, tissue, such as Stiles used, never decreases the conductivity of such dilute solutions, except in experiments of the type which we are trying to explain.

Permeability of egg membranes

1. A method is described for measuring the rate of water exchange through living membranes. 2. By this method definite rates of water exchange forFundulus eggs of different ages were established in solutions oi NaCl, KCl and CaCl2 of various molar concentrations. The effect of these salts in increasing permeability seems to be due to their cations, the order of effectiveness being Na>K>Ca. 3. Marked physiological differences in the membranes of eggs in various developmental stages are indicated. 4. The effect of the hydrogen-ion concentration of the solution on the rates of water exchange is of little significance. 5. Antagonistic effects of mixtures of salts are not evident in the time interval involved in the experiments. 6. The rOles of the chorion and the vitelline membrane in the water and salt exchange of the egg ofFundulus are discussed.