Duodenal brush border intestinal alkaline phosphatase activity affects bicarbonate secretion in rats.

@article{Akiba2007DuodenalBB,
  title={Duodenal brush border intestinal alkaline phosphatase activity affects bicarbonate secretion in rats.},
  author={Yasutada Akiba and Misa Mizumori and Paul H. Guth and Eli Engel and Jonathan D. Kaunitz},
  journal={American journal of physiology. Gastrointestinal and liver physiology},
  year={2007},
  volume={293 6},
  pages={
          G1223-33
        }
}
  • Y. Akiba, M. Mizumori, +2 authors J. Kaunitz
  • Published 1 December 2007
  • Biology, Medicine
  • American journal of physiology. Gastrointestinal and liver physiology
We hypothesized that duodenal HCO(3)(-) secretion alkalinizes the microclimate surrounding intestinal alkaline phosphatase (IAP), increasing its activity. We measured AP activity in rat duodenum in situ in frozen sections with the fluorogenic substrate ELF-97 phosphate and measured duodenal HCO(3)(-) secretion with a pH-stat in perfused duodenal loops. We examined the effects of the IAP inhibitors L-cysteine or L-phenylalanine (0.1-10 mM) or the tissue nonspecific AP inhibitor levamisole (0.1… Expand
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It is suggested that epithelial HCO3- secretion in the duodenal mucosa has a protective function by forming an unstirred alkaline layer at the mucosal surface which impedes the diffusion of luminal acid into the mucosa. Expand
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