Einfluß von Aldosteron auf den Ausstrom markierten Natriums aus den Sammelrohren der Ratte / Influence of aldosterone on ²⁴Na-efflux in collecting ducts of rats

In previous micropuncture studies with collecting ducts from the rat kidney, aldosterone was shown to increase the isotonic sodium reabsorption as well as the transepithelial concentration difference for sodium under steady state conditions with zero net flux. It was thought that the latter effect might have been partially due to a reduced leak permeability for sodium caused by the action of the hormone. To examine this possibility, the 24Na efflux from the collecting duct was studied and found to be decreased by aldosterone. It follows that the hormone must cause a substantial decrease in sodium permeability