The membrane-recruitment-and-recycling hypothesis of gastric HCl secretion.
In the unstimulated oxyntic (or parietal) cell, the primary pump for gastric HCl secretion, the H+/K+-ATPase, is retained within the cytoplasm in a membranous compartment of tubulovesicles. Neural or hormonal stimulation of acid secretion induces extensive membrane transformations consistent with a fusion and recruitment of tubulovesicles to the apical plasma membrane. The consequent placement of H+/K+-ATPase in parallel with K(+) and Cl(-) channels provides the necessary ionic flow and ATP-driven exchange for net HCl secretion. Current evidence is consistent with a recruitment and recycling of membrane transporters, such as H+/K+-ATPase, through docking/fusion machinery analogous to that in many other systems.
Forte
J G
JG
Dept of Molecular and Cell Biology, University of California, Berkeley, CA 94270, USA.
Yao
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