Differential effects of calcium channel antagonists on histamine and pentagastrin-stimulated gastric acid secretion in the rat.

Different calcium channel antagonists have been assessed for their ability to inhibit gastric acid secretion in rats. Whereas verapamil, diltiazem and cinnarizine inhibited pentagastrin-induced gastric acid secretion but not histamine-induced secretion, nifedipine selectively inhibited the stimulant effect of histamine. In contrast, the vasodilator hydralazine had non-selective effects. These findings indicate that calcium-antagonists may have differential effects against different secretagogues and these effects are not simply related to hypotensive effects.