EGF and its related growth factors mediate sodium transport in mpkCCDc14 cells via ErbB2 (neu/HER-2) receptor. J Cell Physiol 2010 Apr;223(1):252-9
Date
01/06/2010Pubmed ID
20049896DOI
10.1002/jcp.22033Scopus ID
2-s2.0-75749109403 (requires institutional sign-in at Scopus site) 25 CitationsAbstract
Amiloride-sensitive sodium entry, via the epithelial sodium channel (ENaC), is the rate-limiting step for Na(+) absorption. Epidermal growth factor (EGF) is involved in the regulation of Na(+) transport and ENaC activity. However it is still controversial exactly how EGF regulates ENaC and Na(+) absorption. The aim of the present study was to characterize the EGF regulation of Na(+) transport in cultured mouse renal collecting duct principal mpkCCD(c14) cells, a highly differentiated cell line which retains many characteristics of the cortical collecting duct (CCD). EGF dose dependently regulates basal transepithelial Na(+) transport in two phases: an acute phase (<4 h) and a chronic phase (>8 h). Similar effects were observed with TGF-alpha, HB-EGF, and amphiregulin which also belong to the EGF-related peptide growth factor family. Inhibition of MEK1/2 by PD98059 or U0126 increased acute effects and disrupted chronic effects of EGF on Na(+) reabsorption. Inhibition of PI3-kinase with LY294002 abolished acute effect of EGF. As assessed by Western blotting, ErbB2 is the most predominant member of the ErbB family detected in mpkCCD(c14) cells. Immunohistochemistry analysis revealed localization of ErbB2 in the CCD in Sprague-Dawley rat kidneys. Both acute and long-term effects of EGF were abolished when cells were treated with tyrphostin AG-825 and ErbB2 inhibitor II, chemically dissimilar selective inhibitors of the ErbB2 receptor. Thus, we conclude that EGF and its related growth factors are important for maintaining transepithelial Na(+) transport and that EGF biphasically modulates sodium transport in mpkCCD(c14) cells via the ErbB2 receptor.
Author List
Levchenko V, Zheleznova NN, Pavlov TS, Vandewalle A, Wilson PD, Staruschenko AMESH terms used to index this publication - Major topics in bold
AmilorideAmphiregulin
Animals
Benzothiazoles
Blotting, Western
Butadienes
Cell Line
Chromones
Dose-Response Relationship, Drug
EGF Family of Proteins
Epidermal Growth Factor
Epithelial Sodium Channels
Flavonoids
Glycoproteins
Heparin-binding EGF-like Growth Factor
Immunohistochemistry
Intercellular Signaling Peptides and Proteins
Ion Transport
Kidney Tubules, Collecting
Kinetics
MAP Kinase Kinase 1
MAP Kinase Kinase 2
Mice
Morpholines
Nitriles
Phosphatidylinositol 3-Kinases
Protein Kinase Inhibitors
Rats
Rats, Sprague-Dawley
Receptor, ErbB-2
Sodium
Sodium Channel Blockers
Transforming Growth Factor alpha
Tyrphostins
