scholarly journals Sodium Transport in the Toad Bladder

1971 ◽  
Vol 28 (5_suppl_2) ◽  
Author(s):  
HOWARD S. FRAZIER
Keyword(s):  
Urinary Bladder ◽  
Sodium Transport ◽  
Mode Of Action ◽  
Renal Tubule ◽  
Alternative Hypothesis ◽  
Toad Bladder ◽  
Second Step ◽  
Epithelial Layer ◽  
Granular Cells ◽  
Simple Alternative

The isolated urinary bladder of the toad transports sodium actively across its epithelial layer and responds to the hormones vasopressin and aldosterone, properties which make it a useful model for the study of certain functions of the renal tubule. Sodium transport in the granular cells of the bladder is thought to involve first an energetically passive but selective entry step at the mucosal surface, the rate of which is increased after vasopressin administration. The second step in transport is considered to be active extrusion of the ion across the serosal boundary of the cell. Recent evidence concerning the cellular pool of sodium and the site and mode of action of vasopressin suggests that this description is at best incomplete. No equally simple alternative hypothesis for the organization of sodium transport in this system is available at present.

Amiloride and the mode of action of aldosterone on sodium transport across toad bladder and skin

1968 ◽  
Vol 304 (3) ◽  
pp. 284-296 ◽  
Author(s):  
Jean Crabb� ◽  
Edward N. Ehrlich ◽  
Jacqueline Scarlata
Keyword(s):  
Sodium Transport ◽  
Mode Of Action ◽  
Toad Bladder

HYALURONIDASE, CORTICOSTEROIDS AND THE ACTION OF NEUROHYPOPHYSIAL HORMONE ON THE URINARY BLADDER OF THE FROG

1962 ◽  
Vol 24 (4) ◽  
pp. 407-413 ◽  
Author(s):  
P. J. BENTLEY
Keyword(s):  
Urinary Bladder ◽  
Sodium Transport ◽  
Mode Of Action ◽  
Normal Rate ◽  
Positive Staining ◽  
Serosal Side ◽  
Neurohypophysial Hormones ◽  
Bovine Testicular Hyaluronidase ◽  
Hyaluronidase Inhibitor ◽  
Testicular Hyaluronidase

SUMMARY 1. The intercellular material of the epithelium of the frog bladder gave a positive staining response for mucopolysaccharides, but bovine testicular hyaluronidase had no effect on its permeability to water or sodium. 2. The hyaluronidase inhibitor 53k decreased the response of the bladder to oxytocin without affecting the normal rate of sodium transport. 3. Cortisol but not aldosterone also reduced responses to oxytocin. 4. Both cortisol and 53k were only effective when placed on the serosal side of the bladder. 5. These results are discussed in relation to the possible mode of action of neurohypophysial hormones.

Mechanism of active chloride transport by urinary bladder of the Colombian toad

1977 ◽  
Vol 233 (5) ◽  
pp. F421-F427
Author(s):  
G. B. Soboslai ◽  
M. McTigue ◽  
M. W. Weiner
Keyword(s):  
Urinary Bladder ◽  
Carbonic Anhydrase ◽  
Ion Transport ◽  
Sodium Transport ◽  
Chloride Transport ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Hydrogen Ion ◽  
Toad Bladder ◽  
Hydrogen Ion Transport

In order to investigate the mechanism of active chloride transport, experiments were performed to verify the previous report that removal of potassium from the solutions bathing the urinary bladders of Colombian toads induced a reversal of short-circuit current (RSCC) and active chloride transport. The present experiments confirmed these findings. However, there was no correlation between the magnitude of the RSCC and the chloride transport. Furthermore, removal of chloride from the mucosal bathing solutions did not markedly affect the RSCC, indicating that the chloride transport was electrically silent. Removal of bicarbonate from the bathing solutions eliminated the RSCC, and acetazolamide inhibited both the RSCC and net chloride transport. These findings suggest a relationship between chloride and hydrogen ion transport. Inhibition of sodium transport by removal of sodium or addition of ouabain or amiloride has previously been shown to produce an RSCC. In the present experiments these same maneuvers caused an RSCC and induced net chloride transport. It is concluded that active chloride transport by Colombian toad bladder is stimulated by inhibition of sodium transport. The inhibition of active chloride transport by acetazolamide suggests a possible role for carbonic anhydrase in this process.

OSMOTIC INHIBITION OF THE NATRIFERIC RESPONSE OF THE TOAD URINARY BLADDER TO VASOPRESSIN

1975 ◽  
Vol 67 (1) ◽  
pp. 119-125
Author(s):  
P. J. BENTLEY
Keyword(s):  
Urinary Bladder ◽  
Water Movement ◽  
Short Circuit ◽  
Electrical Potential ◽  
Short Circuit Current ◽  
Toad Bladder ◽  
Toad Urinary Bladder ◽  
Electrical Potential Difference ◽  
Osmotic Gradient

SUMMARY The electrical potential difference and short-circuit current (scc, reflecting active transmural sodium transport) across the toad urinary bladder in vitro was unaffected by the presence of hypo-osmotic solutions bathing the mucosal (urinary) surface, providing that the transmural flow of water was small. Vasopressin increased the scc across the toad bladder (the natriferic response), but this stimulation was considerably reduced in the presence of a hypo-osmotic solution on the mucosal side, conditions under which water transfer across the membrane was also increased. This inhibition of the natriferic response did not depend on the direction of the water movement, for if the osmotic gradient was the opposite way to that which normally occurs, the response to vasopressin was still reduced. The natriferic response to cyclic AMP was also inhibited in the presence of an osmotic gradient. Aldosterone increased the scc and Na+ transport across the toad bladder but this response was not changed when an osmotic gradient was present. The physiological implications of these observations and the possible mechanisms involved are discussed.

11-Dehydrocorticosterone, a glucocorticoid metabolite, inhibits aldosterone action in toad bladder

1991 ◽  
Vol 261 (5) ◽  
pp. F873-F879 ◽  
Author(s):  
A. S. Brem ◽  
K. L. Matheson ◽  
J. L. Barnes ◽  
D. J. Morris
Keyword(s):  
Sodium Transport ◽  
Cell Layer ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Hydroxysteroid Dehydrogenase ◽  
Toad Bladder ◽  
Compound A ◽  
Dose Dependent Fashion ◽  
Epithelial Cell Layer ◽  
Dose Dependent

The enzyme 11 beta-hydroxysteroid dehydrogenase (11 beta-OHSD) metabolizes glucocorticoid hormones and diminishes their ability to induce sodium transport. In these studies, we determined the location of this enzyme in toad bladder and assessed the biological role for its 11-dehydro end product. Employing a polyclonal antibody directed toward 11 beta-OHSD and immunofluorescence techniques, we located the enzyme in the epithelial cell layer of the toad bladder. Although corticosterone (10(-7) M) can partially suppress aldosterone (10(-7) M)-stimulated short-circuit current (SCC), a clear excess of corticosterone (10(-6) M) did not inhibit the aldosterone-induced induced (10(-8) M) rise in SCC (n = 6). The 11-dehydro product of corticosterone, 11-dehydrocorticosterone (compound A) added to the serosal bath suppressed aldosterone (10(-8) M) peak SCC (360 min) in a dose-dependent fashion reaching 46 +/- 5% of control values at 10(-5) M (n = 6; P less than 0.001). Compound A (10(-5) M) in the mucosal bath also was capable of partially inhibiting the peak aldosterone rise in SCC to 63 +/- 7% of control values with aldosterone at 10(-8) M (n = 6; P less than 0.01) and to 64 +/- 10% of control values with aldosterone at 10(-7) M (n = 9; P less than 0.01). Compound A alone at 10(-5) M did not have any effect on SCC. Isolated toad bladders were not able to transform compound A (at 10(-8) and 10(-5) M) back to corticosterone. Thus the 11-dehydro end product of 11 beta-OHSD (compound A) may play a biologic role by regulating a component of mineralocorticoid-induced sodium transport.

scholarly journals Asymptotic relative submajorization of multiple-state boxes

2021 ◽  
Vol 111 (4) ◽  
Author(s):  
Gergely Bunth ◽  
Péter Vrana
Keyword(s):  
Hypothesis Testing ◽  
Null Hypothesis ◽  
Alternative Hypothesis ◽  
Standard Form ◽  
Point Of View ◽  
State Discrimination ◽  
Simple Alternative ◽  
Multiple State ◽  
Error Probabilities

AbstractPairs of states, or “boxes” are the basic objects in the resource theory of asymmetric distinguishability (Wang and Wilde in Phys Rev Res 1(3):033170, 2019. 10.1103/PhysRevResearch.1.033170), where free operations are arbitrary quantum channels that are applied to both states. From this point of view, hypothesis testing is seen as a process by which a standard form of distinguishability is distilled. Motivated by the more general problem of quantum state discrimination, we consider boxes of a fixed finite number of states and study an extension of the relative submajorization preorder to such objects. In this relation, a tuple of positive operators is greater than another if there is a completely positive trace nonincreasing map under which the image of the first tuple satisfies certain semidefinite constraints relative to the other one. This preorder characterizes error probabilities in the case of testing a composite null hypothesis against a simple alternative hypothesis, as well as certain error probabilities in state discrimination. We present a sufficient condition for the existence of catalytic transformations between boxes, and a characterization of an associated asymptotic preorder, both expressed in terms of sandwiched Rényi divergences. This characterization of the asymptotic preorder directly shows that the strong converse exponent for a composite null hypothesis is equal to the maximum of the corresponding exponents for the pairwise simple hypothesis testing tasks.

scholarly journals Effect of Tetrodotoxin on the Sodium Transport of the Toad Bladder

1967 ◽  
Vol 43 (5) ◽  
pp. 404-406 ◽  
Author(s):  
Fumiaki MARUMO ◽  
Yasushi ASANO ◽  
Takuo SASAOKA ◽  
Shozo KOSHIKAWA
Keyword(s):  
Sodium Transport ◽  
Toad Bladder
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