The cystic fibrosis transmembrane conductance regulator and chloride-dependent ion fluxes of ovine vocal fold epithelium.
J Speech Lang Hear Res
; 52(3): 745-54, 2009 Jun.
Article
en En
| MEDLINE
| ID: mdl-18806217
ABSTRACT
PURPOSE:
Ion-driven transepithelial water fluxes participate in maintaining superficial vocal fold hydration, which is necessary for normal voice production. The authors hypothesized that Cl(-) channels are present in vocal fold epithelial cells and that transepithelial Cl(-) fluxes can be manipulated pharmacologically.METHOD:
Immunohistochemical assays were used to identify cystic fibrosis transmembrane regulator Cl(-) channels in ovine vocal fold mucosae (n = 2). Electrophysiological responses of vocal fold mucosae (n = 80) to Cl(-) channel inhibitors and secretagogues were evaluated in an ovine model using a randomized controlled experimental design.RESULTS:
Cystic fibrosis transmembrane regulator channels were localized to the plasma membranes of epithelial cells. The Cl(-) transport inhibitor, diphenylamine-2-carboxylate, elicited a 30% decrease in mean short-circuit current (I(sc); n = 10). The secretagogue, isobutylmethylxanthine, yielded a 31.7% increase in mean I(sc) (n = 10). Another secretagogue, uridine triphosphate, elicited a 48.8% immediate and 17.3% sustained increase in mean I(sc) (n = 10). No sustained increases occurred following application of secretagogues to mucosae bathed in a low Cl(-) environment (n = 10), suggesting that responses were Cl(-) dependent.CONCLUSIONS:
The authors provide structural and functional evidence for the presence of a transepithelial pathway for Cl(-) fluxes. Pharmacological manipulation of this pathway may offer a mechanism for maintaining superficial vocal fold hydration.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Pliegues Vocales
/
Cloruros
/
Regulador de Conductancia de Transmembrana de Fibrosis Quística
/
Mucosa Laríngea
Límite:
Animals
Idioma:
En
Año:
2009
Tipo del documento:
Article