Gastric H+, K(+)-ATPase inhibition by catechins

J Pharm Pharmacol. 1992 Nov;44(11):926-8. doi: 10.1111/j.2042-7158.1992.tb03238.x.

Abstract

Five catechins, (+)-catechin, (-)-epicatechin, (-)-epicatechin gallate, (-)-epigallocatechin and (-)-epigallocatechin gallate, inhibited gastric H+, K(+)-ATPase activity with IC50 values ranging from 1.7 x 10(-4) to 6.9 x 10(-8) M, with (-)-epigallocatechin gallate as the most potent inhibitor. The intensity of inhibitor activity paralleled the number of phenolic hydroxy groups in the molecule. The inhibition of the enzyme by (-)-epicatechin was competitive with respect to ATP and noncompetitive with respect to K+. These findings suggest that the anti-secretory and anti-ulcerogenic effects of catechins previously reported, are due to their inhibitory activity on gastric H+, K(+)-ATPase.

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Animals
  • Catechin / analysis
  • Catechin / pharmacology*
  • In Vitro Techniques
  • Proton Pump Inhibitors*
  • Stomach / enzymology*
  • Swine

Substances

  • Proton Pump Inhibitors
  • Adenosine Triphosphate
  • Catechin