Effect of salvianolic acid A, a depside from roots of Salvia miltiorrhiza, on gastric H+,K(+)-ATPase.

Salvianolic acid A, a depside from the roots of Salvia miltiorrhiza, inhibited pig gastric H+,K(+)-ATPase and pNPPase with 50% inhibition values (IC50) of 5.2 x 10(-7) M and 1.7 x 10(-6) M, respectively. Kinetic studies revealed that the inhibition patterns induced by salvianolic acid A were competitive with respect to ATP and noncompetitive with respect to K+. Salvianolic acid A (25 mg/kg, i.p.) significantly inhibited acid secretion in pylorus-ligated rats. At the same dose it also showed a significant reduction in the formation of gastric lesion induced by water immersion and restraint stress. These results suggest that salvianolic acid A shows antisecretory and antiulcer activity by inhibiting the gastric H+,K(+)-ATPase.