Identification of the K efflux channel coupled to the gastric H-K-ATPase during acid secretion.
نویسندگان
چکیده
Genomic microarray analysis of genes specifically expressed in a pure cell isolate from a heterocellular organ identified the likely K efflux channel associated with the gastric H-K-ATPase. The function of this channel is to supply K to the luminal surface of the pump to allow H for K exchange. KCNQ1-KCNE2 was the most highly expressed and significantly enriched member of the large variety of K channels expressed in the gastric epithelium. The function of this K channel in acid secretion was then shown by inhibition of secretion in isolated gastric glands with specific KCNQ inhibitors and by colocalization of the channel with the H-K-ATPase in the secretory canaliculus of the parietal cell. KCNQ1-KCNE2 appears to be the K efflux channel that is essential for gastric acid secretion.
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یافته های تازه درباره سلولهای پاریتال معده
During the last five years the recognition of ionic channels in the parietal cells of stomach and acid chloride mechanisms of secretion by these cells has become totally clear by the "Patch Oamp" technique. The apical cytoplasm in the oxyntic cells are in the form of vesicles where membranes contain H+, K+ -ATPase pump. Stimulation causes fusion of these tubular vesicles with the cell membran o...
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عنوان ژورنال:
- Physiological genomics
دوره 21 1 شماره
صفحات -
تاریخ انتشار 2005