Effects of 12-sulfodehydroabietic acid monosodium salt (TA-2711), a new anti-ulcer agent, on gastric secretion and experimental ulcers in rats

Effects of 12-sulfodehydroabietic acid monosodium salt (TA-2711), a new anti-ulcer agent, on gastric secretion and experimental ulcers were investigated in rats. Oral administration of TA-2711 at doses of 25 to 100 mg/kg immediately after pyloric ligation markedly reduced pepsin activity and slightly lowered acid concentration without affecting the volume of gastric juice. Addition of TA-2711 (0.25-16 mg/ml) directly to gastric juice also reduced pepsin activity in vitro. Oral TA-2711 dose-relatedly inhibited the formation of pylorus-ligated ulcers (50-200 mg/kg), aspirin-induced gastric erosions (25-100 mg/kg) and cysteamine-induced duodenal ulcers (100-800 mg/kg). In addition, this drug prevented both the formation of gastric lesions (6.3-100 mg/kg, p.o.) and the fall in gastric potential difference (100 mg/kg, p.o.) induced by ethanol. The preventive effect against ethanol-induced lesions was suppressed by pretreatment with indomethacin (10 mg/kg, s.c.). Intravenous dosing of TA-2711 (10-100 mg/kg) never produced such effects on ethanol-induced lesions and pepsin activity as observed by oral administration. These results indicate that TA-2711 exerts its anti-ulcer effect by a local action, and it is suggested that both reduction of pepsin activity and a mucosal prostaglandin-mediated process are involved in the anti-ulcer action of TA-2711.