Effect of 3-[p-(trans-4-aminomethylcyclohexylcarbonyl)phenyl]propionic acid hydrochloride on gastric mucosal barrier

Effects of 3-p-(trans-4-aminomethylcyclohexylcarbonyl)phenyl]propionic acid hydrochloride (TEI-5103, TG-51) on mucosal protection, ion permeability, potential difference, glycoprotein content, and bicarbonate secretion as parameters of the mucosal barrier in rats were studied. TEI-5103 (50-400 mg/kg p.o.) prevented the formation of gastric lesions induced by 75% ethanol, 0.6N HCl, and 0.1N HCl + 60% ethanol. Indometacin (10 mg/kg s.c.) given 30 min prior to TEI-5103 dosing slightly attenuated this protective effect. TEI-5103 (20 mg/ml intragastrically) prevented the increase in acid back-diffusion and ion permeability induced by acetylsalicylic acid (ASA, 5 mg/kg intragastrically). It also inhibited the decrease in mucosal potential difference induced by ASA and resultant lesion formation at 1 h after ASA dosing. TEI-5103 (400 mg/kg p.o.) improved the decrease in mucosal high molecular glycoprotein content induced by ASA (100 mg/kg p.o.), whereas it did not change the normal mucosal glycoprotein content. By intra-luminal perfusion of TEI-5103 (10 and 20 mg/ml/min), an increase in CO2 concentration in the perfusate was observed, suggesting heightened bicarbonate secretion. Its effect at 20 mg/ml/min was same as that of prostaglandin E2 (20 micrograms/ml/min). These findings suggest that TEI-5103 has a cytoprotective effect like prostaglandin and promotes the integrity of the mucosal barrier. These effects of TEI-5103 may contribute to its overall anti-ulcer effect.