Autoradiographic studies of solute transport across the toad bladder

Autoradiographic studies of solute transport across the toad bladder.

The autoradiography of diffusible, hydrophilic solutes presents special problems in localization of the labeled solute under study. We present studies of the movement of 14C-labeled urea, and 14C- and 3H-labeled sucrose across the isolated urinary bladder of the toad, a vasopressin-sensitive epithelium, using a technique that avoids exposure to water throughout all processing steps and minimize...

The Action of Aldosterone and Related Corticosteroids on Sodium Transport across the Toad Bladder.

The importance of aldosterone and related adrenal steroids in the regulation of renal conservation of Na+ and excretion of K+ has been established by extensive studies in man and other mammals (1). The complexity of the mammalian kidney, however, makes it difficult to study the chemical pathways involved in the action of mineralocorticoids on cation transport. The prospects for achieving a solu...

Active Solute Transport across Frog

Diffusion of Weak Acids across the Toad Bladder

Studies have been carried out, using the toad bladder, to determine the influence of pH on the permeability coefficients (K(trans)) of the non-ionic species of (a) a series of aliphatic acids ranging from propionic to octanoic and (b) the aromatic acids, benzoic and acetylsalicylic. The data demonstrate that as the acidity of the mucosal bathing solution is increased by changing pH from 6 to 4,...

The Kinetics of Sodium Transport in the Toad Bladder

In the accompanying paper, a compartmental model for the toad bladder sodium transport system was developed. In the present paper, the model is tested by determining the effects of antidiuretic hormone on the pools and fluxes. It is shown that this hormone affects only that sodium pool previously designated as the transport pool, and that the effects are on two separate sites. In the first plac...