ENaC inhibition stimulates HCl secretion in the mouse cortical collecting duct. I. Stilbene-sensitive Cl- secretion.
Am J Physiol Renal Physiol
; 309(3): F251-8, 2015 Aug 01.
Article
em En
| MEDLINE
| ID: mdl-25925258
ABSTRACT
Inhibition of the epithelial Na(+) channel (ENaC) reduces Cl(-) absorption in cortical collecting ducts (CCDs) from aldosterone-treated rats and mice. Since ENaC does not transport Cl(-), the purpose of the present study was to explore how ENaC modulates Cl(-) absorption in mouse CCDs perfused in vitro. Therefore, we measured transepithelial Cl(-) flux and transepithelial voltage in CCDs perfused in vitro taken from mice that consumed a NaCl-replete diet alone or the diet with aldosterone administered by minipump. We observed that application of an ENaC inhibitor [benzamil (3 µM)] to the luminal fluid unmasks conductive Cl(-) secretion. During ENaC blockade, this Cl(-) secretion fell with the application of a nonselective Cl(-) channel blocker [DIDS (100 µM)] to the perfusate. While single channel recordings of intercalated cell apical membranes in split-open CCDs demonstrated a Cl(-) channel with properties that resemble the ClC family of Cl(-) channels, ClC-5 is not the primary pathway for benzamil-sensitive Cl(-) flux. In conclusion, first, in CCDs from aldosterone-treated mice, most Cl(-) absorption is benzamil sensitive, and, second, benzamil application stimulates stilbene-sensitive conductive Cl(-) secretion, which occurs through a ClC-5-independent pathway.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Cloretos
/
Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico
/
Bloqueadores dos Canais de Sódio
/
Ácido Clorídrico
/
Túbulos Renais Coletores
Tipo de estudo:
Diagnostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article