Reabsorptive response of renal tubules to elevated sodium and chloride concentrations in plasma

Sustained and relatively constant levels of hypernatremia and hyperchloremia were obtained by infusing dogs with 150 ml of 5% or 10% sodium chloride solutions for 30 minutes and following this with infusions of 0.85% sodium chloride at the rate of 5 ml/min. Inulin clearances and serum and urinary sodium and chloride values were determined during a number of periods when plasma sodium and chloride were at normal or near normal values and compared with similar determinations made after hypertonic saline infusions when plasma sodium and chloride were at high but relatively steady levels. For any given rate of glomerular filtration more sodium chloride was reabsorbed at high plasma salt levels than at normal or near normal levels. Moreover, the rate of reabsorption increases as plasma sodium and chloride increase. The enhanced tubular reabsorptive activity toward sodium chloride at a time when a large surfeit of salt exists appears paradoxical when viewed as a consequence of active transport processes. On the other hand, these results are precisely what would be predicted if passive reabsorption of glomerular filtrate occurred in an area of the tubule freely permeable to salt as well as water.

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GERMINATION OF ALFALFA VARIETIES IN SOLUTIONS OF VARYING OSMOTIC PRESSURE AND RELATIONSHIP TO WINTER HARDINESS

Canadian Journal of Plant Science ◽

10.4141/cjps59-051 ◽

1959 ◽

Vol 39 (3) ◽

pp. 384-394 ◽

Cited By ~ 13

Author(s):

D. H. Heinrichs

Keyword(s):

Sodium Chloride ◽

Osmotic Pressure ◽

Laboratory Experiments ◽

Reliable Method ◽

Winter Hardiness ◽

The Other ◽

General Tendency ◽

Salt Solutions ◽

Sodium Chloride Solutions ◽

Alfalfa Varieties

Two laboratory experiments were conducted to evaluate the reliability of amount of germination in solutions of varying osmotic pressure, as a means of separating alfalfa varieties into winter-hardiness classes. In one test 23 varieties or strains were studied, and in the other 36. It was found that significant differences exist between certain alfalfa varieties in their ability to germinate in sucrose or sodium chloride solutions of 3, 6, and 9 atmospheres. There is a general tendency for non-hardy varieties to germinate more rapidly and more completely than hardy ones but there are many exceptions to this trend. Germination in solutions of 6 atmospheres osmotic pressure at 5 days gave the best separation of varieties on the basis of their ability to germinate. Germination was generally better in solutions of sucrose at 6 atmospheres osmotic pressure than in solutions of sodium chloride of the same osmotic pressure but several varieties germinated equally well in either solution. The results indicate that germinating alfalfa in sugar or salt solutions is not a reliable method for differentiating alfalfa varieties into winter hardiness classes.

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Exchangeable sodium pool size and sodium turnover in freshwater- and saltwater-acclimated ducks and gulls

Canadian Journal of Zoology ◽

10.1139/z84-310 ◽

1984 ◽

Vol 62 (11) ◽

pp. 2142-2145 ◽

Cited By ~ 18

Author(s):

Juliet R. Roberts ◽

Maryanne R. Hughes

Keyword(s):

Sodium Chloride ◽

Body Mass ◽

Turnover Rate ◽

Plasma Osmolality ◽

Pool Size ◽

Plasma Sodium ◽

Exchangeable Sodium ◽

Body Sodium ◽

Sodium Flux ◽

Chloride Concentrations

The exchangeable sodium pool size and its turnover rate were determined in ducks, Anas platyrhynchos, and gulls, Larus glaucescens, acclimated to freshwater and subsequently to 2/3 seawater. Saline acclimation led to a significant reduction in body mass in ducks but not gulls. Exchangeable body sodium per unit wet body mass was significantly greater for gulls (43 mmol∙kg−1) than for ducks (30 mmol∙kg−1) drinking freshwater. It was not significantly different between saltwater-acclimated ducks (48 mmol∙kg−1) and gulls (44 mmol∙kg−1). Saline drinking increased the sodium pool of ducks but not gulls. Similarly, the sodium flux per unit body mass was significantly higher for freshwater gulls (4.2 mmol∙kg−1∙day−1) than for ducks (2.1 mmol∙kg−1∙day−1). It was not significantly different between saltwater gulls (19 mmol∙kg−1∙day−1) and ducks (21 mmol∙kg−1∙days−1). Saline acclimation increased sodium flux by a factor of 4.5 for gulls and 10.4 for ducks. Freshwater-acclimated gulls had significantly higher levels of plasma sodium, chloride, and osmolality than did ducks. Saline acclimation increased the plasma osmolality of both species and the sodium and chloride concentrations of the plasma of ducks, and it decreased the hematocrit of ducks. Hematocrit and plasma osmotic and ionic concentrations were similar for saline-acclimated gulls and ducks.

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Is 3α-androstanediol a marker of peripheral hirsutism?

Acta Endocrinologica ◽

10.1530/acta.0.0990314 ◽

1982 ◽

Vol 99 (2) ◽

pp. 314-320 ◽

Cited By ~ 22

Author(s):

Vincenzo Toscano ◽

Francesco Sciarra ◽

Maria Vittoria Adamo ◽

Elisa Petrangeli ◽

Sonia Foli ◽

...

Keyword(s):

Chromatographic Separation ◽

Plasma Levels ◽

Normal Values ◽

Plasma Concentrations ◽

High Plasma ◽

The Other ◽

Dehydroepiandrosterone Sulphate ◽

Group I ◽

Group Ii ◽

Peripheral Origin

Abstract. The behaviour of 5α-reduced metabolites of testosterone, dihydrotestosterone1, 3α-androstanediol and 3β-androstanediol, was studied in 36 hirsute women: Group I: 24 patients with high plasma levels of testosterone, androstenedione and/or dehydroepiandrosterone sulphate and Group II: 12 patients with normal plasma concentrations of these steroids. Testosterone and its 5α-reduced metabolites were determined by radioimmunoassay after chromatographic separation on celite 535 microcolumns. Plasma 3α-androstanediol was found to be elevated both in Group I (26.9 ± 10.8 sd ng/100 ml) and in Group II patients (23.2 ± 10.5 sd ng/100 ml). 3β-Androstanediol and dihydrotestosterone, on the contrary, were elevated in only a few cases: in 6 cases in Group I and in 2 and in 1 case, respectively, in Group II. The finding of high plasma 3α-androstanediol levels in hirsute women, with normal values of the other androgens, may be an index of hirsutism of peripheral origin, since this steroid is produced almost exclusively in the extraglandular compartment.

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STUDIES IN EDEMA

Journal of Experimental Medicine ◽

10.1084/jem.11.3.480 ◽

1909 ◽

Vol 11 (3) ◽

pp. 480-488

Author(s):

Moyer S. Fleisher ◽

Leo Loeb

Keyword(s):

Sodium Chloride ◽

Calcium Chloride ◽

Chloride Solution ◽

Sodium Chloride Solution ◽

Marked Decrease ◽

Specific Effect ◽

The Other ◽

Intestinal Fluid ◽

Endothelial Lining ◽

Sodium Chloride Solutions

1. Animals in which experimental myocarditis has been produced and winch are infused with sodium chloride solutions show a marked decrease in the amount of the secretion of urine. This decrease is even more pronounced than that produced when calcium chloride is added to sodium chloride solution. The intestinal fluid which is markedly decreased, and the peritoneal transudate which is increased by calcium chloride are, on the other hand, not markedly influenced by myocarditic lesions. We may, therefore, conclude that calcium chloride does not exert its specific effect on the quantity of peritoneal fluid through a lowering of blood pressure. 2. Each of the three factors, namely, calcium chloride, adrenalin and myocarditic lesions affects the elimination of fluid through the kidneys, through the mucosa of the small intestine and through the endothelial lining of the peritoneal cavity in a specific way. The conditions influencing the elimination of fluids through these three surfaces seem, therefore, to be different in each case and characteristic for the cells lining these surfaces.

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