A possible mechanism for the gastric mucosal protection by Oren-gedoku-to(OGT), a traditional herbal medicine.

Abstract

We investigated the involvement of sulfhydryl-compounds in the cytoprotective effect of Oren-gedoku-to (OGT) against ethanol-induced gastric lesions and potential difference (PD) reduction in comparison with those of sucralfate and glutathione in rats. Pretreatment with indomethacin (IND) had little influence on the cytoprotective effects of OGT and glutathione, but attenuated the effect of sucralfate. Pretreatment with N-ethylmaleimide (NEM) blocked the cytoprotective effects of these three drugs. Pretreatment with iodoacetamide diminished the cytoprotection of OGT and glutathione, but had little effect on that of sucralfate. The cytoprotective activities of OGT, glutathione and sucralfate were little affected by pretreatment with 6,6'-dithiodinicotinic acid. The inhibitory effects of OGT and glutathione against the PD reduction were completely blocked by pretreatment with NEM, while they were not influenced by pretreatment with IND. On the other hand, the inhibitory effect of sucralfate disappeared both by IND and NEM. These results suggest that the cytoprotective effect of OGT may be mediated by endogenous sulfhydryl compounds, but not by endogenous prostaglandins in the gastric mucosa.