Luminal hydrochloric acid stimulates rapid transepithelial ion fluxes in rodent esophageal stratified squamous epithelium

• Autorzy: Lin B.R. , Hsieh H.T. , Lee J.M. , Lai I.R. , Chen C.F. , Yu L.C.H.
• Języki publikacji: EN

Abstrakty

EN

It remains unclear whether enhanced ion fluxes occur in the esophageal stratified squamous epithelium upon acid exposure. Rat esophageal tissues devoid of submucosal glands displayed basal short-circuit current (Isc) of 5.03 ± 1.93 µA/cm2 and lumen-negative potential difference (PD) in association with net absorption of Na+ and Cl-, and secretion of HCO3-. Luminal hydrochloric acid (HCl) challenge (pH = 1.6) triggered an acute rise of the Isc and increment of negative PD to seven-fold of baseline, which was diminished in HCO3--free, but not Na+- free buffer. The rise of Isc was inhibited by pretreatment with di-isothiocyanatostilbene-2, 2'-disulphonic acid (DIDS) and 5-(N-ethyl-N-isopropyl)-amiloride (EIPA). Topical carbachol, capsaicin, forskolin or CFTRinh-172 had no effect on basal Isc. CFTRinh-172 did not reduce the acid-increased Isc. Functional ablation of capsaicin-sensitive nerves had no effect on the acid-induced Isc. The phenomenon of enhanced ion fluxes upon acid stimulation was confirmed in human esophageal specimens. Our results demonstrated that the mechanism of acid-induced rapid transepithelial ion fluxes is dependent on the presence of bicarbonate ions as well as functional anion transporters and Na+/H+ exchanger, but independent of cystic fibrosis transmembrane conductance regulator (CFTR). The capsaicin-sensitive and muscarinic-dependent nerve pathways did not play roles in the mechanism.

Słowa kluczowe

EN

ion transport; cystic fibrosis transmembrane conductance regulator; rodent; oesophageal epithelium; rat; bicarbonate ion; hydrochloric acid

• Wydawca: -
• Czasopismo: Journal of Physiology and Pharmacology
• Rocznik: 2008
• Tom: 59
• Numer: 3
• Opis fizyczny: p.525-542,fig.,ref.

Twórcy

autor

Lin B.R.

• National Taiwan University College of Medicine, No.1, Section 1, Jen-Ai Road, Taipei 100, Taiwan

autor

Hsieh H.T.

autor

Lee J.M.

autor

Lai I.R.

autor

Chen C.F.

autor

Yu L.C.H.