Sodium and water transport in single perfused distal tubules of Necturus kidney

Maude, DL; Shehadeh, Isam H.; Ak, Solomon

doi:10.1152/ajplegacy.1966.211.4.1043

Cited by 12 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A consideration of both distal tubular free-flow and steady-state concentra-tions ratios of sodium confirms previous results (Bott, 1962;Maude et al, 1966) that this tubular segment establishes significant concentration differences for this ion species. Similar results obtain in the mammalian distal tubule (Malnic et al, 1966 a, b;Giebisch and Windhager, 1964).…”

Section: Discussionsupporting

confidence: 86%

“…It is also apparent that the direction of net transfer of potassium across this nephron segment changes as a function of the metabolic situation. Furthermore, the results obtained during free flow of tubular fluid and in the series of stationary microperfusion experiments demonstrate that the distal tubular epithelium establishes potassium concentrations significantly lower than could be expected from the observed transepithelial potential difference (see also Maude et al, 1966). The observed transepithelial potassium concentration ratios are even considerably below those expected on the basis of passive distribution according to the electrical driving force under conditions of maximal potassium secretion; i.e., in animals which had been exposed to a high-K environment or had been given a carbonic anhydrase inhibitor.…”

Section: Discussionmentioning

confidence: 87%

“…Information on the role of the distal tubule in sodium and potassium excretion by amphibian nephrons is much less extensive (Bott, 1962;Maude et al, 1966), particularly with respect to changes in transport patterns induced by different metabolic demands. The recent observation by Sullivan (1968) that the ventral portion of Amphiuma kidneys is made up predominantly of distal tubules has prompted the present investigation which takes advantage of a number of unusual properties of this amphibian kidney.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Potassium and Sodium Transport across Single Distal Tubules of Amphiuma

Wiederholt

Sullivan

Giebisch

1971

The Journal of General Physiology

View full text Add to dashboard Cite

The transport properties of potassium (K) and sodium (Na) were studied in single distal tubules of Amphiuma using free-flow micropuncture techniques and stationary microperfusion methods. The transepithelial movement of labeled potassium was measured utilizing a three-compartment system in series in which the time course of tracer disappearance from the lumen was followed. Under control conditions, in blood-and doubly-perfused kidneys, extensive active net reabsorption of sodium and potassium obtains along single distal tubules. Tubular potassium reabsorption is abolished by ouabain at a concentration of 5 X 10-6

show abstract

Section: Discussionsupporting

confidence: 86%

Section: Discussionmentioning

confidence: 87%

mentioning

confidence: 99%

See 1 more Smart Citation

Potassium and Sodium Transport across Single Distal Tubules of Amphiuma

Wiederholt

Sullivan

Giebisch

1971

The Journal of General Physiology

View full text Add to dashboard Cite

show abstract

“…In the distal tubules, reabsorption is no longer isotonic, but can continue until quite a large osmotic differential has been established. In Necturus, Maude, Shehadeh & Solomon (1966) showed that in the presence of a non-transported non-electrolyte to impede water uptake, the luminal [Na] could be reduced down to 9 mM. In mammals the sodium concentration gradient at the far end of the distal tubule may reach 120 mM.…”

Section: Water Movementsmentioning

confidence: 99%

From frog skin to sheep rumen: a survey of transport of salts and water across multicellular structures

Keynes¹

1969

Quart. Rev. Biophys.

136

View full text Add to dashboard Cite

All higher animals, whether they live in water or on dry land, are faced with the necessity of regulating rather closely their intake and excretion of salts and water in order to maintain the constancy of their internal ionic environment. The kidney is in general the most important organ of the body as far as the excretion of sodium, potassium, chloride and water is concerned, but there are other tissues which also play a part in controlling the ionic balance between the internal and external environments, such as the intestinal mucosa, the skin and urinary bladder in amphibia, the gill epithelium in fishes, the salt gland in marine birds, and the epithelium of the rumen in ruminants. In addition to excretory and absorptive organs of this type, there are others which are secretory and whose function involves the production of fluids differing in ionic composition from the blood plasma. Examples include the glands which secrete saliva and sweat, the oxyntic acid-producing cells of the gastric mucosa, and the epithelium of the stria vascularis which generates the potassium-rich endolymph of the mammalian cochlea. The purpose of this article is to consider briefly what is known about the active transport of salts and water across some typical multicellular secretory tissues, and to attempt in the process to discern what properties they have in common and in what respects they are specialized.

show abstract

“…Anders liegen die Verh~ltnisse fiir das Kalium. Wird mit K+-freien LSsungen perfundiert, dann kommt es zur K+-KonzentrationserhShung im Perfusat bis zum Konzentrationsausgleieh mit dem Plasma [6]. Die Nephrone yon Necturus und die lqieren yon Rana ridibunda verhalten sich demnaeh so, als ob sie im Richtungssinne der Sekretion fiir I~a + impermeabel w/~ren.…”

Section: Tubul~re Wasser-subs~anzbewegungen Durch Osmo~ische Gradien~unclassified

Tubuläre Wasser- und Substanzbewegungen infolge artifizieller transcellulärer osmotischer Gradienten bei Rana ridibunda

Vogel¹,

Latka²,

Richter³

1968

Pflugers Arch.

View full text Add to dashboard Cite

Osmotic gradients of 150 mosmol/1 between intratubular fluid and blood in the kidney of Rana ridibunda induce a fluid movement down the osmotic gradient which is stronger into the tubule than out of it. In either case Na + is reabsorbed "dry' '.If the active Na+-transport is blocked by Furosemid an osmotically downhill movement of isotonic fluid out of the tubule obtains. Reversal of the osmotic gradient induces a reversal of flow but the inward moving fluid is diluted. The tubular cells seem to inhibit the backwash of Na+. If the osmotic gradient induces an outflow of fluid out of the tubule no influx of l~a+ occurs even in the presence of a concentration gradient for Na + in the opposite direction. The Na+-concentration in the urine falls considerably below that of the pcrfusion fluid. This finding indicates Na +-reabsorption against a concentration gradient. Upon blocking of the Na+-transport by Furosemid water enters the tubules.The results of the experiments in which the Na+-transport was blocked by Furosemid prove that the tubules are impermeable for Na+ in the direction of secretion. The "dilution" of the tubular fluid as a result of an osmotic gradient which induces an influx of water is not due to a reabsorption outbalancing "secretion".If instead of the easily penetrating NaC1 the slowly penetrating Na+-cyclohexanesulphamate is used, less Na + is transported. However, in every other respect the results obtained are similar to those described above.Zusammen]assung. Dutch artifizielle osmotische Druckdifferenzen yon 150 mOsmol/1 zwischen Lumen-und Blutseite der Tubulusepithelien yon Rana ridibunda wird Fliissigkeit im Richtungssirme der l~eabsorption oder --in geringerem MaBe --der Sekretion l~ngs des osmotischen Gradienten bewegt. Na + wird in jedem Fall ,,trocken" reabsorbiert.Bei mit Furoscmid blockicrtem aktiven Na+-Transport l~uft isoton Fliissigkeit l~ngs des osmotischen Gradienten aus dem Tubuluslumen in das blutseitige Medium. Bei umgekehrt gerichtetem Gradicnten wird das Filtrat so ver~ndert, als ob es dutch Einstrom reinen Wassers verdiinnt wiirde. Die Tubulusepithelien verhalten sich so, als bes~Ben sie --im Zustand des blockierten aktiven Na+-Transportes --ein ,,Riickschlagventil" fiir lga+. Wena der osmotische Gradient so gerichtet ist, dais Wasser oder Fliissigkeit aus dem Lumen in das blutseitige Medium l~uft, dalm

show abstract

Sodium and water transport in single perfused distal tubules of Necturus kidney

Cited by 12 publications

References 0 publications

Potassium and Sodium Transport across Single Distal Tubules of Amphiuma

Potassium and Sodium Transport across Single Distal Tubules of Amphiuma

From frog skin to sheep rumen: a survey of transport of salts and water across multicellular structures

Tubuläre Wasser- und Substanzbewegungen infolge artifizieller transcellulärer osmotischer Gradienten bei Rana ridibunda

Contact Info

Product

Resources

About