Correlation Engine 2.0
Clear Search sequence regions

Sizes of these terms reflect their relevance to your search.

The kidney needs to adapt daily to variable dietary K+ contents via various mechanisms including diuretic, acid-base and hormonal changes that are still not fully understood. In this study, we demonstrate that following a K+-deficient diet in wildtype mice, the serine protease CAP2/Tmprss4 is upregulated in connecting tubule and cortical collecting duct and also localizes to the medulla and transitional epithelium of the papilla and minor calyx. Male CAP2/Tmprss4 knockout mice display altered water handling and urine osmolality, enhanced vasopressin response leading to upregulated adenylate cyclase 6 expression and cAMP overproduction, and subsequently greater aquaporin 2 (AQP2) and Na+-K+-2Cl- cotransporter 2 (NKCC2) expression following K+-deficient diet. Urinary acidification coincides with significantly increased H+,K+-ATPase type 2 (HKA2) mRNA and protein expression, and decreased calcium and phosphate excretion. This is accompanied by increased glucocorticoid receptor (GR) protein levels and reduced 11β-hydroxysteroid dehydrogenase 2 activity in knockout mice. Strikingly, genetic nephron-specific deletion of GR leads to the mirrored phenotype of CAP2/Tmprss4 knockouts, including increased water intake and urine output, urinary alkalinisation, downregulation of HKA2, AQP2 and NKCC2. Collectively, our data unveil a novel role of the serine protease CAP2/Tmprss4 and GR on renal water handling upon dietary K+ depletion.


Anna Keppner, Darko Maric, Chloé Sergi, Camille Ansermet, Damien De Bellis, Denise V Kratschmar, Jérémie Canonica, Petra Klusonova, Robert A Fenton, Alex Odermatt, Gilles Crambert, David Hoogewijs, Edith Hummler. Deletion of the serine protease CAP2/Tmprss4 leads to dysregulated renal water handling upon dietary potassium depletion. Scientific reports. 2019 Dec 20;9(1):19540

Expand section icon Mesh Tags

Expand section icon Substances

PMID: 31863073

View Full Text