Calcium, carbonic anhydrase and gastric acid secretion
Jazyk angličtina Země Česko Médium print
Typ dokumentu klinické zkoušky, časopisecké články, randomizované kontrolované studie
PubMed
11551141
Knihovny.cz E-zdroje
- MeSH
- chelátory aplikace a dávkování MeSH
- dospělí MeSH
- EDTA aplikace a dávkování MeSH
- erytrocyty enzymologie MeSH
- karboanhydrasa II metabolismus MeSH
- karboanhydrasa IV metabolismus MeSH
- koncentrace vodíkových iontů MeSH
- lidé středního věku MeSH
- lidé MeSH
- nervus vagus fyziologie MeSH
- vápník aplikace a dávkování krev MeSH
- žaludeční kyselina metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- klinické zkoušky MeSH
- randomizované kontrolované studie MeSH
- Názvy látek
- chelátory MeSH
- EDTA MeSH
- karboanhydrasa II MeSH
- karboanhydrasa IV MeSH
- vápník MeSH
Previous data concerning the action of calcium (Ca) on gastric acid secretion (GAS) indicated that calcium ions increase GAS elicited by gastrin released through a vagal mechanism, and also by a direct effect on parietal cells. Our research showed that the stimulating effect of calcium on gastric acid secretion can be antagonized by verapamil administration, which reduces gastric acid secretion . In the present study we followed the effect induced by administration of calcium and Ca-chelating agents (disodium EDTA) on gastric acid secretion and on carbonic anhydrase (CA) activity. We selected two groups of healthy volunteers: Group I (n=21) received a single i.v. dose of CaCl2 (15 mg/kg b.w.), whereas Group II (n=22) received a single i.v. dose of disodium EDTA (5 mg/kg b.w.). We determined blood calcium before and after treatment, gastric acid secretion at 2 hours. erythrocyte CA II activity, and CA IV activity in membrane parietal cells, which were isolated from gastric mucosa obtained by endoscopic biopsy. Assessment of carbonic anhydrase activity was achieved by the stopped-flow method. In Group I calcium administration increased blood calcium, HCl output, CA II and CA IV activity as compared to initial values. In Group II, disodium EDTA reduced blood calcium, HCl output, CA II and CA IV activity as compared to initial values. The results demonstrated that increased blood calcium and GAS values after calcium administration correlated with the increase of erythrocyte CA II and parietal cell CA IV activity, while disodium EDTA induced a reversed process. Our results also show that cytosolic CA II and membrane CA IV values are sensitive to calcium changes and they directly depend on these levels. Our data suggest that intra- and extracellular pH changes induced by carbonic anhydrase might account for the modulation of the physiological and pathological secretory processes in the organism.