PT - JOURNAL ARTICLE AU - BENS, MARCELLE AU - VALLET, VÉRONIQUE AU - CLUZEAUD, FRANÇOISE AU - PASCUAL-LETALLEC, LAURENT AU - KAHN, AXEL AU - RAFESTIN-OBLIN, MARIE E. AU - ROSSIER, BERNARD C. AU - VANDEWALLE, ALAIN TI - Corticosteroid-Dependent Sodium Transport in a Novel Immortalized Mouse Collecting Duct Principal Cell Line DP - 1999 May 01 TA - Journal of the American Society of Nephrology PG - 923--934 VI - 10 IP - 5 4099 - http://jasn.asnjournals.org/content/10/5/923.short 4100 - http://jasn.asnjournals.org/content/10/5/923.full SO - J. Am. Soc. Nephrol.1999 May 01; 10 AB - Abstract. The final control of sodium balance takes place in the cortical collecting duct (CCD) of the nephron, where corticosteroid hormones regulate sodium reabsorption by acting through mineralocorticoid (MR) and/or glucocorticoid (GR) receptors. A clone of principal CCD cells (mpkCCDc14) has been established that is derived from a transgenic mouse (SV40 large T antigen under the control of the SV40 enhancer/L-type pyruvate kinase promoter). Cells grown on filters form polarized monolayers with high electrical transepithelial resistance (RT approximately 4700 Ω × cm2) and potential difference (PD approximately -50 mV) and have an amiloride-sensitive electrogenic sodium transport, as assessed by the short-circuit current method (Isc approximately 11 μA/cm2). Reverse transcription-PCR experiments using rat MR primers, [3H]aldosterone, and [3H]dexamethasone binding and competition studies indicated that the mpkCCDc14 cells exhibit specific MR and GR. Aldosterone increased Isc in a dose- (10-10 to 10-6 M) and time-dependent (2 to 72 h) manner, whereas corticosterone only transiently increased Isc (2 to 6 h). Consistent with the expression of 11β-hydroxysteroid dehydrogenase type 2, which metabolizes glucocorticoids to inactive 11-dehydroderivates, carbenoxolone potentiated the corticosterone-stimulated Isc. Aldosterone (5 × 10-7 M)-induced Isc (fourfold) was associated with a three- to fivefold increase in α-ENaC mRNA (but not in those for β- or γ-ENaC) and three- to 10-fold increases in α-ENaC protein synthesis. In conclusion, this new immortalized mammalian CCD clonal cell line has retained a high level of epithelial differentiation and sodium transport stimulated by aldosterone and therefore represents a useful mammalian cell system for identifying the genes controlled by aldosterone.