Relationship of Renal Sodium and Water Transport to Hydrogen Ion Secretion

Isolated bullfrog tadpole stomachs secrete H+ by stage XXIV of metamorphosis, when tail reabsorption is nearly complete. At this stage the PD shows characteristic responses identical to those of the adult. The appearance of HCl secretion correlates well with other studies showing the morphogenesis of oxyntic cells. Prior to the development of H+ secretion tadpole stomachs maintain a PD similar in polarity and magnitude to that of the adult; i.e., secretory (S) side negative with respect to the nutrient (N) side. The interdependence with aerobic metabolism appeared to increase progressively through metamorphosis; however, glycolytic inhibitors always abolished the PD. Isotopic flux analysis showed that the transepithelial movement of Na+ was consistent with passive diffusion, whereas an active transport of Cl- from N to S was clearly indicated. Variations in [Na+], [K+], and [Cl-] in the bathing solutions induced changes consistent with the following functional description of the pre-H+-secreting tadpole stomach. (a) The S side is relatively permeable to Cl-, but not to Na+ or K+. (b) An equilibrium potential for K+ and Cl- exists at the N interface. (c) Ouabain abolishes the selective K+ permeablity at the N interface and reduces the total PD. (d) Effects of Na+ replacement by choline in the N solution become manifest only below 10–20 mM. It is concluded that prior to development of H+ secretion, the tadpole gastric PD is generated by a Cl- pump from N to S and a Na+ pump operating from the cell interior toward the N side.

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A Role of Cyclic AMP in the Gastrointestinal Tract: Receptor Control of Hydrogen Ion Secretion by Mammalian Gastric Mucosa

Handbook of Experimental Pharmacology - Cyclic Nucleotides ◽

10.1007/978-3-642-68393-0_16 ◽

1982 ◽

pp. 651-682 ◽

Cited By ~ 3

Author(s):

W. J. Thompson ◽

E. D. Jacobson ◽

G. C. Rosenfeld

Keyword(s):

Gastrointestinal Tract ◽

Gastric Mucosa ◽

Cyclic Amp ◽

Hydrogen Ion ◽

Ion Secretion

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New Insights into the Physiology of Peritoneal Fluid Transport

Peritoneal Dialysis International ◽

10.1177/089686080802803s27 ◽

2008 ◽

Vol 28 (3_suppl) ◽

pp. 144-149

Author(s):

Raymond T. Krediet ◽

Annemieke M. Coester ◽

Alena Parikova ◽

Watske Smit ◽

Dirk G. Struijk

Keyword(s):

Water Transport ◽

Fluid Transport ◽

Free Water ◽

Osmotic Gradient ◽

Ultrafiltration Failure ◽

Ultra Filtration ◽

Relationship Of ◽

The Relationship

A review is given on the mechanisms of free water transport, the various methodologies for its measurement, its dependency on the osmotic gradient, and the assessment of osmotic conductance in individual patients. The importance of impaired free water transport in long-term ultra-filtration failure is discussed, relative to peritoneal solute transport status. Furthermore, the relationship of free water transport with locally released potassium is considered, together with a potential role of impaired K+ channel function with peritoneal alterations. Finally, the role of impaired osmotic conductance to glucose and its effects on free water transport in long-term patients with ultrafiltration failure is reviewed.

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Relationship between potassium, acid secretion and bioelectric potentials of frog gastric mucosa in the presence of histamine and thiocyanate

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1959.196.6.1266 ◽

1959 ◽

Vol 196 (6) ◽

pp. 1266-1269 ◽

Cited By ~ 7

Author(s):

John B. Harris ◽

Isidore S. Edelman

Keyword(s):

Gastric Mucosa ◽

Acid Secretion ◽

Potassium Concentration ◽

Hydrogen Ion ◽

Ion Secretion ◽

Transient Rise ◽

Net Flux ◽

Bioelectric Potentials ◽

Sustained Increase

The transmucosal potential difference (PD), the rate of H+ secretion and the net flux of potassium from nutrient to secretory phases (JnsK) of the frog gastric mucosa were studied in vitro by the chamber method. Histamine produced a fall in PD, a sustained increase in H+ production and an equivocal rise in JnsK. Increasing the nutrient potassium concentration (Kn) to 8.5 mEq/l. in the presence of histamine induced a depression in PD, although the rate of acid secretion was unchanged. Hydrogen ion secretion decreased when the nutrient potassium concentration was decreased to 1 mEq/l. despite the continued presence of histamine. The response of JnsK to alterations in nutrient potassium concentration was unaffected by the presence of either histamine or thiocyanate. Thiocyanate produced almost complete inhibition of H+ secretion and a rise in PD. Raising the nutrient potassium concentration in the presence of thiocyanate produced a prompt and sustained fall in PD, followed by a transient rise when Kn was lowered. Alterations of the nutrient potassium concentration in the presence of thiocyanate had no effect on the rate of acidification. The data indicate that under certain circumstances PD and H+ secretion can be uncoupled and that the inverse relationship between Kn and PD is substantially independent of the rate of H+ secretion.

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NH4+ transport in acid-secreting insect epithelium

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1988.254.2.r348 ◽

1988 ◽

Vol 254 (2) ◽

pp. R348-R356 ◽

Cited By ~ 6

Author(s):

R. B. Thomson ◽

J. M. Thomson ◽

J. E. Phillips

Keyword(s):

Amino Acids ◽

Apical Membrane ◽

Schistocerca Gregaria ◽

Hydrogen Ion ◽

Ph Gradients ◽

Ussing Chambers ◽

Ion Secretion ◽

Acid Secreting ◽

Ph Range ◽

The Relationship

The relationship between ammonia secretion (JAmm), hydrogen ion secretion (JH), and intracellular pH (pHi) was investigated in isolated locust (Schistocerca gregaria) rectal epithelia mounted as flat sheets in specially designed Ussing chambers. In the absence of exogenous CO2 and ammonia, the rectum is capable of net acid and ammonia secretion into the lumen against pH gradients of up to 1.8 U. JAmm was dependent on the presence of luminal amino acids and Na+ and it was relatively unaffected by K+ removal or changes in membrane potential. JAmm and pHi remained fairly constant over a luminal pH range of 7-5, whereas JH decreased linearly to zero over the same pH range. Mucosal addition of 1 mM amiloride reduced JAmm by 60%. This study demonstrates that the locust rectum secretes significant quantities of endogenously produced ammonia preferentially into the lumen as NH+4 rather than NH3. Moreover, the results suggest that the ammonia crosses the apical membrane via an amiloride-inhibitable Na+-NH+4 exchange mechanism.

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Studies on the regulation of hydrogen ion secretion in the collecting duct in vivo: Evaluation of factors that influence the urine minus blood PCO2 difference

Kidney International ◽

10.1038/ki.1981.187 ◽

1981 ◽

Vol 20 (5) ◽

pp. 636-642 ◽

Cited By ~ 9

Author(s):

Siu-Cheung Tam ◽

Marc B. Goldstein ◽

Bobby J. Stinebaugh ◽

Ching-Bun Chen ◽

André Gougoux ◽

...

Keyword(s):

Collecting Duct ◽

Hydrogen Ion ◽

In Vivo Evaluation ◽

Ion Secretion

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Kinetics of aquation of the fluoropentaamminecobalt(III) ion

Canadian Journal of Chemistry ◽

10.1139/v70-175 ◽

1970 ◽

Vol 48 (7) ◽

pp. 1054-1058 ◽

Cited By ~ 13

Author(s):

T. W. Swaddle ◽

W. E. Jones

Keyword(s):

Ionic Strength ◽

Rate Coefficient ◽

Hydrogen Ion ◽

Fluoride Ion ◽

Kcal Mole ◽

First Order ◽

Order Rate ◽

Relationship Of ◽

The Relationship ◽

Kinetics Of

The kinetics of the hydrogen-ion-independent pathway for the replacement of fluoride in aqueous (NH3)5CoF2+ by H2O have been reinvestigated using a specific fluoride-ion electrode, with due regard for the concomitant autocatalytic loss of the ammine ligands. In perchlorate media of ionic strength 0.1 M, the first-order rate coefficient is 1.22 × 10−6 s−1 at 45°, and the kinetics are represented by ΔH* = 24.4 kcal mole−1 and ΔS* = −9 cal deg−1 mole−1 over the range 35–75° at least. The relationship of these data to those for the aquation of other species of the type ML5Xn+ is discussed.

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