Université de Fribourg

αENaC mediated lithium absorption promotes nephrogenic diabetes insipidus

Mønster Christensen, Birgitte ; Mercier Zuber, Annie ; Loffing, Johannes ; Stehle, Jean-Christophe ; Deen, Peter M.T. ; Rossier, Bernard C. ; Hummler, Edith

In: Journal of the American Society of Nephrology, 2010, vol. 21, p. -

Lithium-induced nephrogenic diabetes insipidus (NDI) is accompanied by polyuria, downregulation of aquaporin 2 (AQP2), and cellular remodeling of the collecting duct (CD). The amiloride-sensitive epithelial sodium channel (ENaC) is a likely candidate for lithium entry. Here, we subjected transgenic mice lacking αENaC specifically in the CD (knockout [KO] mice) and littermate controls to chronic...

Université de Fribourg

In vivo nuclear translocation of mineralocorticoid and glucocorticoid receptors in rat kidney: differential effect of corticosteroids along the distal tubule

Ackermann, Daniel ; Gresko, Nikolay ; Carrel, Monique ; Loffing-Cueni, Dominique ; Habermehl, Daniel ; Gomez-Sanchez, Celso ; Rossier, Bernard C. ; Loffing, Johannes

In: American Journal of Physiology - Renal Physiology, 2011, vol. 299, no. 6, p. F1473-F1485

Aldosterone and corticosterone bind to mineralocorticoid (MR) and glucocorticoid receptors (GR), which, upon ligand binding, are thought to translocate to the cell nucleus to act as transcription factors. Mineralocorticoid selectivity is achieved by the 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) that inactivates 11β-hydroxy glucocorticoids. High expression levels of 11β-HSD2...

Université de Fribourg

Progesterone down-regulates the open probability of the amiloride-sensitive epithelial sodium channel via a Nedd4-2-dependent mechanism

Michlig, Stéphanie ; Harris, Michael ; Loffing, Johannes ; Rossier, Bernard C. ; Firsov, Dmitri

In: Journal of Biological Chemistry, 2005, vol. 280(46), p. 38264

Activation of the mitogen-activated protein (MAP) kinase cascade by progesterone in Xenopus oocytes leads to a marked down-regulation of activity of the amiloride-sensitive epithelial sodium channel (ENaC). Here we have studied the signaling pathways involved in progesterone effect on ENaC activity. We demonstrate that: (i) the truncation of the C termini of the αβγENaC subunits results...