Details

Autor(en) / Beteiligte

• Garcia, Mary Abigail S
• Yang, Ning
• Quinton, Paul M

Titel

Normal mouse intestinal mucus release requires cystic fibrosis transmembrane regulator-dependent bicarbonate secretion

Ist Teil von

• The Journal of clinical investigation, 2009-09, Vol.119 (9), p.2613-2622

Ort / Verlag

United States: American Society for Clinical Investigation

Erscheinungsjahr

2009

Link zum Volltext

Quelle

EZB Free E-Journals

Beschreibungen/Notizen

• The mechanisms underlying mucus-associated pathologies in cystic fibrosis (CF) remain obscure. However, recent studies indicate that CF transmembrane conductance regulator (CFTR) is required for bicarbonate (HCO3-) transport and that HCO3- is critical for normal mucus formation. We therefore investigated the role of HCO3- in mucus secretion using mouse small intestine segments ex vivo. Basal rates of mucus release in the presence or absence of HCO3- were similar. However, in the absence of HCO3-, mucus release stimulated by either PGE2 or 5-hydroxytryptamine (5-HT) was approximately half that stimulated by these molecules in the presence of HCO3-. Inhibition of HCO3- and fluid transport markedly reduced stimulated mucus release. However, neither absence of HCO3- nor inhibition of HCO3- transport affected fluid secretion rates, indicating that the effect of HCO3- removal on mucus release was not due to decreased fluid secretion. In a mouse model of CF (mice homozygous for the most common human CFTR mutation), intestinal mucus release was minimal when stimulated with either PGE2 or 5-HT in the presence or absence of HCO3-. These data suggest that normal mucus release requires concurrent HCO3- secretion and that the characteristically aggregated mucus observed in mucin-secreting organs in individuals with CF may be a consequence of defective HCO3- transport.