The gastric anti-ulcer activity of naringenin, a specific histidine decarboxylase inhibitor.

The gastric anti-ulcer activity of a specific histidine decarboxylase inhibitor naringenin, the aglycone of naringin, a naturally occurring flavanone glycoside obtained from kino and grapefruits, has been studied on the various types of ulcers experimentally induced in rats, viz., pylorus-ligated (Shay method) and restraint ulcers, and on the gastric mucosal damage induced by aspirin, phenylbutazone or reserpine. Naringenin possessed significant anti-ulcer activity in all these models, manifesting a dose-dependent anti-ulcer effect on the pylorus-ligated and restraint ulcers. However, the ED50 value against ulcers in the pylorus-ligated rats (132 mg/kg) was significantly greater than that against ulcers in the restraint rats (42 mg/kg). Amongst all the models used, naringenin was found most effective against the restraint rats. It is suggested that a mechanism involving the inhibition of formation and release of endogenous histamine in the gastric mucosa of rats is implicated in the protective effect of naringenin.