Journal
CELL BIOLOGY INTERNATIONAL
Volume 29, Issue 7, Pages 559-566Publisher
WILEY
DOI: 10.1016/j.cellbi.2005.03.010
Keywords
NTPDase; stomach; extracellular ATP; ectonucleotidases; apyrase
Categories
Ask authors/readers for more resources
The degradation of nucleotides is catalyzed by the family of enzymes called nucleoside triphosphate diphosphohydrolases (NTPDases). The aim of this work was to demonstrate the presence of NTPDase in the rat gastric mucosa. The enzyme was found to hydrolyze ATP and ADP at an optimum pH of 8.0 in the presence of Mg2+ and Ca2+. The inhibitors ouabain (0.01-1 mM), N-ethylmaleimide (0.01-4 mM), levamisole (0.10-0.2 mM) and Ap(5)A (0.03 mM) had no effect on NTPDase I activity. Sodium azide (0.03-30 mM), at high concentrations (> 0.1 mM), caused a parallel hydrolysis inhibition of ATP and ADP. Suramin (50-300 mu M) inhibited ATP and ADP hydrolysis at all concentrations tested. Orthovanadate slightly inhibited (15%) Mg2+ and Ca2+ + ATP/ADPase at 100 mu M. Lanthanum decreased Mg2+ and Ca2+ ATP/ADPase activities. The presence of NTPDase as ecto-enzyme in the gastric mucosa may have an important role in the extracellular metabolism of nucleotides, suggesting that this enzyme plays a role in the control of acid and pepsin secretion, mucus production, and contractility of the stomach. (c) 2005 International Federation for Cell Biology. Published by Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available