Reduction of centrally-stimulated gastric acid secretion by tizanidine, a new imidazoline derivative, in anesthetized rats.

The effect of a novel imidazoline derivative (tizanidine) on stimulated gastric acid secretion was studied in the perfused stomach of anesthetized rats. Tizanidine, which did not prevent peripherally-stimulated gastric acid secretion, inhibited 2DG- or TRH-stimulated gastric acid secretion. Yohimbine and phentolamine reduced the inhibition of TRH-stimulated acid secretion by tizanidine. Clonidine was found to have similar effects to tizanidine at a lower dose. These results indicate that tizanidine may inhibit gastric acid secretion via the central alpha-adrenergic system similar to clonidine in anesthetized rats.