Role of the inhibitory effect of tetrodotoxin on the active sodium transport of the toad bladder

1968 ◽  
Vol 303 (1) ◽  
pp. 49-54 ◽  
Author(s):  
F. Marumo ◽  
T. Yamada ◽  
Y. Asano ◽  
T. Sasaoka ◽  
A. Yoshida ◽  
...  
Keyword(s):  
Sodium Transport ◽  
Inhibitory Effect ◽  
Toad Bladder ◽  
Active Sodium ◽  
Active Sodium Transport

The inhibitory effect of reserpine on the active sodium transport across the frog bladder

1976 ◽  
Vol 365 (1) ◽  
pp. 15-19 ◽  
Author(s):  
Fumiaki Marumo ◽  
Takao Mishina ◽  
Yasushi Asano ◽  
Yohtalou Tashima
Keyword(s):  
Sodium Transport ◽  
Inhibitory Effect ◽  
Active Sodium ◽  
Active Sodium Transport

scholarly journals The Electrical Characteristics of Active Sodium Transport in the Toad Bladder

1963 ◽  
Vol 46 (3) ◽  
pp. 491-503 ◽  
Author(s):  
Howard S. Frazier ◽  
Alexander Leaf
Keyword(s):  
Sodium Transport ◽  
Short Circuit ◽  
Diffusion Potential ◽  
Toad Bladder ◽  
Chloride Diffusion ◽  
Active Sodium ◽  
High Potassium ◽  
Potential Step ◽  
Active Sodium Transport ◽  
Wide Range

The mechanism responsible for active sodium transport in the urinary bladder of the toad appears to be located at the serosal boundary of the epithelial cell layer of the bladder. Studies of the potential step observed at the serosal boundary in the open-circuited state were undertaken in an attempt to define the factors responsible for its production. Glass micropipettes were used to measure the serosal potential step in bladders exposed on the serosal side to solutions of high potassium or of high potassium and low chloride concentration. Observed potentials exceed the maximum values which would have been expected if the serosal potential step were a potassium or chloride diffusion potential. Measurements of net cation flux exclude the possibility of a diffusion potential at this border due to the passive movement of any anionic species. The observed independence of transbladder potential and short-circuit current from the pH of the serosal medium over a wide range of pH makes it unlikely that the observed serosal potential step is a hydrogen ion diffusion potential. We conclude that the active sodium transport mechanism in toad bladder is "electrogenic."

scholarly journals THE EFFECT OF CALCIUM WITHDRAWAL ON THE STRUCTURE AND FUNCTION OF THE TOAD BLADDER

1965 ◽  
Vol 25 (3) ◽  
pp. 195-209 ◽  
Author(s):  
Richard M. Hays ◽  
Bayla Singer ◽  
Sasha Malamed
Keyword(s):  
Epithelial Cells ◽  
Sodium Transport ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Structure And Function ◽  
Toad Bladder ◽  
Active Sodium ◽  
Bathing Medium ◽  
Active Sodium Transport ◽  
And Function

Previous reports have indicated that calcium is necessary to support active sodium transport by the toad bladder, and may be required as well in the action of vasopressin on both toad bladder and frog skin. The structure and function of the toad bladder has been studied in the absence of calcium, and a reinterpretation of the previous findings now appears possible. When calcium is withdrawn from the bathing medium, epithelial cells detach from one another and eventually from their supporting tissue. The short-circuit current (the conventional means of determining active sodium transport) falls to zero, and vasopressin fails to exert its usual effect on short-circuit current and water permeability. However, employing an indirect method for the estimation of sodium transport (oxygen consumption), it is possible to show that vasopressin exerts its usual effect on Qoo2 when sodium is present in the bathing medium. Hence, it appears that the epithelial cells maintain active sodium transport when calcium is rigorously excluded from the bathing medium, and continue to respond to vasopressin. The failure of conventional techniques to show this can be attributed to the structural alterations in the epithelial layer in the absence of calcium. These findings may provide a model for the physiologic action of calcium in epithelia such as the renal tubule.

scholarly journals Correction: The Role of Angiotensin II and Cyclic AMP in Alveolar Active Sodium Transport

PLoS ONE ◽  
2015 ◽  
Vol 10 (8) ◽  
pp. e0137118 ◽  
Author(s):  
Reem Ismael-Badarneh ◽  
Julia Guetta ◽  
Geula Klorin ◽  
Gidon Berger ◽  
Niroz Abu-saleh ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Cyclic Amp ◽  
Sodium Transport ◽  
Active Sodium ◽  
Active Sodium Transport
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