Inhibition of H⁺, K⁺-ATPase by Methyl(E)-2-(3, 4-Dimethoxystyryl)-Benzimidazole-4-Carboxylate (ALE-36)

Abstract

ALE-36, as well as omeprazole and SCH 28080, markedly inhibited the [^l4C]aminopyrine (AP) accumulation induced by dibutyryl cyclic AMP (dbcAMP) and H⁺, K⁺-ATPase activity in a concentration-dependent manner. The inhibitory effect of omeprazole on the dbcAMP-induced [¹⁴C]AP accumulation was reversed by treatment with β-mercaptoethanol, but those of ALE-36 and SCH 28080 were not. ALE-36 and SCH 28080 did not inhibit dog renal Na⁺, K⁺-ATPase activity, while omeprazole and ouabain did inhibit this enzyme activity. These results suggest that the inhibitory action of ALE-36 on acid secretion is due to the specific inhibition of gastric H⁺, K⁺-ATPase, the manner being different from in the case of omeprazole.

Key Words:

• ALE-36
• K⁺-ATPase
• H⁺, Na⁺, K⁺-ATPase
• omeprazole
• SCH 28080