Nitecapone effect on the synthesis and secretion of gastric sulfomucin

Abstract

1. 1. The effect of a new antiulcer agent, nitecapone, on the synthesis and secretion of sulfomucin in gastric mucosa was investigated using mucosal segments incubated in the presence of [ 3H]proline, [ 3H]glucosamine and [ 35S]sulfate. 2. 2. The drug, while showing no discernible effect on the apomucin synthesis, evoked a dose-dependent increase in mucin glycosylation and sulfation, which at 225 μM nitecapone, attained its maximum of 1.8 and 2.2-fold stimulation, respectively. 3. 3. The analysis of mucin secretory responses revealed that nitecapone caused a concentration-dependent enhancement in sulfomucin secretion attaining maximum increase of 1.5-fold at 150 μM nitecapone. 4. 4. The stimulatory effect of nitecapone on sulfomucin secretion was accompanied by 1.4-fold increase in mucosal cAMP level, and showed sensitivity to protein kinase A inhibitors, thus pointing towards the involvement of protein kinase A in mediation of gastric sulfomucin secretory responses to nitecapone. 5. 5. The ability of nitecapone to enhance sulfomucin synthesis and secretion could be of importance to the gastroprotective action of this agent.