These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Mechanism of the inhibition of hog gastric H+,K(+)-ATPase by the seleno-organic compound ebselen.
    Author: Tabuchi Y, Ogasawara T, Furuhama K.
    Journal: Arzneimittelforschung; 1994 Jan; 44(1):51-4. PubMed ID: 8135879.
    Abstract:
    The effect of 2-phenyl-1,2-benzisoselenazol-3 (2H)-one (ebselen, CAS 60940-34-3), a seleno-organic compound, on the partial reaction steps of H+,K(+)-ATPase in hog leaky gastric vesicles was examined. Ebselen inhibited K(+)-dependent ATPase activity (IC50 = 0.06 mumol/l), phosphoenzyme formation (IC50 = 0.25 mumol/l), and K(+)-dependent p-nitrophenylphosphatase activity (IC50 = 0.09 mumol/l: dephosphorylation step of this enzyme). Furthermore, this compound prevented changes in the fluorescence intensity of flourescein isothiocyanate-labeled enzyme (E1-->E2K form, IC50 = 0.33 mumol/l). Pretreatment with 2 mmol/l of dithiothreitol (DTT) used as a sulfhydryl compound completely protected against these inhibitory effects. These findings indicate that ebselen-induced inactivation of gastric H+,K(+)-ATPase may result from prevention of the partial reaction steps, which include phosphorylation, dephosphorylation and conformational change (E1-->E2K form), through interference with sulfhydryl groups of the enzyme.
    [Abstract] [Full Text] [Related] [New Search]