Effect of hypoosmotic shock on the volume of renal collecting duct epithelial cells of brattleboro rats with hereditarily defective vasopressin synthesis

This study determined whether nucleotides that bind to purinergic receptors (P2R) regulate the expression or function of serum- and glucocorticoid-inducible kinase-1 (SGK1) in mouse renal inner medullar collecting duct cells (mIMCD-3). The SGK1 protein was detected by Western blotting. A significant reduction of cytosolic SGK1 expression was observed in the cells pretreated with P2R agonist adenosine 5′- O-(3-thiotriphosphate) (ATPγS), and the reduction could be reversed by P2R antagonists. This reduction was also observed in cells that were pretreated with agonists for P2R subtypes. Using ELISA, we observed a reduced SGK1 kinase activity in ATPγS-pretreated cells. This effect was reversed by P2R antagonists. Furthermore, an increase of SGK1 kinase activity in aldosterone-pretreated cells was suppressed by ATPγS. These studies demonstrate for the first time that SGK1 can be downregulated by nucleotides in renal collecting duct epithelial cells, likely via the activation of P2R, and suggest that activation of renal purinergic signaling regulates a SGK1-dependent pathway that is known to modulate ion transport in the renal collecting duct.

Download Full-text

Faculty Opinions recommendation of Renal collecting duct epithelial cells regulate inflammation in tubulointerstitial damage in mice.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.13357214.14726566 ◽

2011 ◽

Author(s):

Hayo Castrop

Keyword(s):

Epithelial Cells ◽

Collecting Duct ◽

Tubulointerstitial Damage ◽

Renal Collecting Duct

Download Full-text

Renal collecting duct epithelial cells regulate inflammation in tubulointerstitial damage in mice

Journal of Clinical Investigation ◽

10.1172/jci57582 ◽

2011 ◽

Vol 121 (9) ◽

pp. 3425-3441 ◽

Cited By ~ 150

Author(s):

Katsuhito Fujiu ◽

Ichiro Manabe ◽

Ryozo Nagai

Keyword(s):

Epithelial Cells ◽

Collecting Duct ◽

Tubulointerstitial Damage ◽

Renal Collecting Duct

Download Full-text

Conditional gene expression in renal collecting duct epithelial cells: use of the inducible Cre-lox system

AJP Renal Physiology ◽

10.1152/ajprenal.00301.2002 ◽

2004 ◽

Vol 286 (1) ◽

pp. F180-F187 ◽

Cited By ~ 15

Author(s):

Antoine Ouvrard-Pascaud ◽

Stefania Puttini ◽

Yannis Sainte-Marie ◽

Rafika Athman ◽

Virginie Fontaine ◽

...

Keyword(s):

Epithelial Cells ◽

Structure Function ◽

Mineralocorticoid Receptor ◽

Hormone Receptors ◽

Fluorescent Protein ◽

Collecting Duct ◽

Expression System ◽

Selection Marker ◽

Cellular Models ◽

Renal Collecting Duct

The renal collecting duct plays a key role in control of ion and fluid homeostasis. Genes encoding for ion transporters, hormone receptors, or regulatory proteins specifically expressed in the collecting duct are mutated in several genetic diseases with altered blood pressure. Suitable cellular models expressing genes in a conditional way should represent attractive systems for structure-function analyses and generation of appropriate physiopathological models of related diseases. However, generation of such systems remains laborious and quite inefficient. We adapted and improved a conditional Cre-lox-inducible system in the highly differentiated aldosterone-sensitive rat cortical collecting duct (RCCD2) cell line. The inducible MerCreMer recombinase allowed tight control and high levels of transgene expression, whereas flanking a selection marker with two loxP sites strongly improved the selection procedure. We have used this system to conditionally express an enhanced green fluorescent protein-tagged human mineralocorticoid receptor. In the future, this will allow structure-function analyses as well as mineralocorticoid receptor trafficking studies in these epithelial cells, which retain the features of the native collecting duct. Improvements in the conditional Cre-lox expression system have potentially wide applications in other epithelial or nonepithelial cell lines.

Download Full-text

Expression of an AQP2 Cre recombinase transgene in kidney and male reproductive system of transgenic mice

AJP Cell Physiology ◽

10.1152/ajpcell.1998.275.1.c216 ◽

1998 ◽

Vol 275 (1) ◽

pp. C216-C226 ◽

Cited By ~ 110

Author(s):

Raoul D. Nelson ◽

Peter Stricklett ◽

Corrine Gustafson ◽

Anna Stevens ◽

Dennis Ausiello ◽

...

Keyword(s):

Epithelial Cells ◽

Transgenic Mice ◽

Vas Deferens ◽

Collecting Duct ◽

Cre Recombinase ◽

Principal Cell ◽

Rt Pcr ◽

Specific Expression ◽

Flanking Region ◽

Renal Collecting Duct

A transgenic mouse approach was used to examine the mechanism of principal cell-specific expression of aquaporin-2 (AQP2) within the renal collecting duct. RT-PCR and immunocytochemistry revealed that murine AQP2 was expressed in principal cells in the renal collecting duct, epithelial cells of the vas deferens, and seminiferous tubules within testis. The vas deferens expression was confirmed in rats. RT-PCR and immunocytochemistry showed that 14 kb of the human 5′-flanking region confers specific expression of a nucleus-targeted and epitope-tagged Cre recombinase in the principal cells within the renal collecting duct, in the epithelial cells of the vas deferens, and within the testis of transgenic mice. These results suggest that cell-specific expression of AQP2 is mediated at the transcriptional level and that 14 kb of the human AQP2 5′-flanking region contain cis elements that are sufficient for cell-specific expression of AQP2. Finally, renal principal cell expression of Cre recombinase is the first step in achieving cell-specific gene knockouts, thereby allowing focused examination of gene function in this cell type.

Download Full-text