Evidence for a chloride conductance in secretory membrane of parietal cells
| Autor: | Aura Perez, S. J. Hersey, G. Sachs, D. Blissard |
|---|---|
| Rok vydání: | 1989 |
| Předmět: |
Physiology
Protonophore In Vitro Techniques Salicylanilides Ion Channels Valinomycin chemistry.chemical_compound Chlorides Parietal Cells Gastric Chloride Channels Physiology (medical) Gastric glands medicine Animals Secretion Hepatology Acridine orange Cell Membrane Gastroenterology Imidazoles Conductance Membrane Proteins Models Theoretical Anti-Ulcer Agents Kinetics Membrane medicine.anatomical_structure Spectrometry Fluorescence chemistry Biochemistry Gastric Mucosa Chloride channel Biophysics Rabbits |
| Zdroj: | The American journal of physiology. 256(2 Pt 1) |
| ISSN: | 0002-9513 |
| Popis: | A fluorescence-quench method using acridine orange as the probe was employed to monitor acid formation in situ by detergent-permeabilized gastric glands. In KCl medium, the addition of ATP to the permeabilized glands resulted in a rapid decrease in fluorescence and addition of valinomycin resulted in a second phase of fluorescence quench. The fluorescence was restored by addition of the H+-K+-ATPase inhibitor, Sch 28080. An ATP-dependent fluorescence quench was observed also in K2SO4 or K+-isethionate medium; however, valinomycin was ineffective in the Cl-free media. The ATP-dependent quench could be reversed or prevented by the electrogenic protonophore, tetrachlorosalicylanilide (TCS), in KCl medium but not in Cl-free media. The results with TCS are interpreted as demonstrating a large Cl- conductance in the secretory membrane, whereas the results with valinomycin indicate that resting membranes lack a K+ conductance. The data suggest that a complex KCl pathway that may demonstrate a Cl- conductance is used to activate acid secretion. |
| Databáze: | OpenAIRE |
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