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Updated: Aug 20, 2026

Profiling Luminal pH in Three-Dimensional Gastrointestinal Organoids Using Microelectrodes
Published on: July 5, 2024
Carbonic anhydrases in normal gastrointestinal tract and gastrointestinal tumours
Antti-J Kivelä1, Jyrki Kivelä, Juha Saarnio
1Department of Anatomy and Cell Biology, University of Oulu, Finland. antti.j.kivela@fimnet.fi
Abstract:
Carbonic anhydrases (CAs) catalyse the hydration of CO2 to bicarbonate at physiological pH. This chemical interconversion is crucial since HCO3- is the substrate for several biosynthetic reactions. This review is focused on the distribution and role of CA isoenzymes in both normal and pathological gastrointestinal (GI) tract tissues. It has been known for many years that CAs are widely present in the GI tract and play important roles in several physiological functions such as production of saliva, gastric acid, bile, and pancreatic juice as well as in absorption of salt and water in intestine. New information suggests that these enzymes participate in several processes that were not envisioned earlier. Especially, the recent reports on plasma membrane-bound isoenzymes IX and XII have raised considerable interest since they were reported to participate in cancer invasion and spread. They are induced by tumour hypoxia and may also play a role in von Hippel-Lindau (VHL)-mediated carcinogenesis.
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