Effects of the antiulcer drug geranylgeranylacetone on aspirin-induced gastric ulcers in rats.

Antiulcer effects of geranylgeranylacetone (GGA) on aspirin-induced gastric ulcers in rats were studied, comparing them with those of gefarnate. The oral administration of GGA prevented the development of gastric ulcer induced by a single or repeated oral administration (5 consecutive days) of aspirin. The effects of GGA were more potent and more definite than those of gefarnate. The intraduodenal administration of GGA, but not the intragastric administration, also inhibited the ulceration induced by aspirin in pylorus-ligated rats, while the intraduodenal administration of gefarnate did not. GGA prevented the reduction of the H+ concentration and the increment of Na+ concentration in the gastric juice induced by aspirin. In addition, the decrease of hexosamine content in the gastric mucosa induced by aspirin was restored to a normal level by GGA, but not by gefarnate. From these results, it was concluded that the protective actions of GGA on aspirin-induced gastric ulcers might be due to its protection from the weakening of gastric mucosal resistances.