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Vacuolar-type H+-ATPase-mediated proton transport in the rat parietal cell.
Kopic, S; Wagner, ME; Griessenauer, C; Socrates, T; Ritter, M; Geibel, JP;
Pflugers Arch. 2012; 463(3):419-427
Originalarbeiten (Zeitschrift)


Griessenauer Christoph
Ritter Markus


The vacuolar-type H-ATPase (V-ATPase) plays an important role in the active acidification of intracellular organelles. In certain specialized cells, such as the renal intercalated cell, apical V-ATPase can also function as a proton secretion pathway. In the parietal cells of the stomach, it has been thought that acid secretion is controlled solely via the H,K-ATPase. However, recent observations suggest that functional V-ATPase is necessary for acid secretion to take place. This study aimed to investigate and characterize the role of V-ATPase in parietal cell proton transport. Individual rat gastric glands were incubated with the pH-sensitive dye (BCECF) to monitor changes in intracellular pH in real time. Parietal cell V-ATPase activity was measured by quantifying the rate of intracellular alkalinization (ΔpH/minute) following an acid load, while excluding the contribution of non-V-ATPase proton transport mechanisms through pharmacological inhibition or ion substitution. Expression of V-ATPase was confirmed by immunohistochemistry. We observed concanamycin A-sensitive V-ATPase activity in rat parietal cells following intracellular acidification and H,K-ATPase inhibition. Furthermore, V-ATPase-mediated proton transport could be abolished by inhibiting trafficking mechanisms with paclitaxel and by stimulating H,K-ATPase with acid secretagogues. Our results propose that parietal cells contain a functional V-ATPase that can be mobilized using a microtubule network. V-ATPase may function as an auxiliary acid secretion or proton-buffering pathway in parietal cells, which is inactive during H,K-ATPase activity. Our findings may have important implications for patients experiencing acid breakthrough under proton pump inhibitor therapy.

Useful keywords (using NLM MeSH Indexing)





Ion Transport


Parietal Cells, Gastric/drug effects

Parietal Cells, Gastric/metabolism*


Proton-Motive Force


Rats, Sprague-Dawley

Vacuolar Proton-Translocating ATPases/antagonists*


Vacuolar Proton-Translocating ATPases/metabolism*

Find related publications in this database (Keywords)

Ion transport
Acid secretion
Vacuolar-type H+-ATPase
Acid breakthrough