High baseline ROMK activity in the mouse late distal convoluted and early connecting tubule probably contributes to aldosterone-independent K<sup>+</sup> secretion
Viatcheslav Nesterov, Marko Bertog, Christoph Korbmacher
Abstract
ROMK-mediated renal K + secretion is essential for maintaining K + balance and requires a lumen negative transepithelial potential critically dependent on activity of the ENaC. Using microdissected distal mouse tubules, we demonstrated that baseline apical ROMK activity is high in the DCT2/CNT. Aldosterone-independent baseline ENaC activity is also high in the DCT2/CNT and downregulated by a low-K + diet, which highlights the important role of the DCT2/CNT in regulating K + secretion in an aldosterone-independent manner.
Topics & Concepts
AldosteroneEpithelial sodium channelSecretionInternal medicineEndocrinologyDistal convoluted tubuleReabsorptionChemistryHyperkalemiaPseudohypoaldosteronismMineralocorticoidKidneyBiologyMedicineSodiumOrganic chemistryIon Transport and Channel RegulationIon channel regulation and functionReceptor Mechanisms and Signaling