Restorative impact of rabeprazole on gastric mucus and mucin production impairment during naproxen administration: its potential clinical significance.

Rabeprazole augments gastric mucus and mucin production in humans. However, its potential restorative impact on gastric mucus and mucin production impairment, resulting from administration of naproxen, remained to be explored. Therefore, we measured the content of mucus and mucin in gastric juice (GJ) before and after administration of naproxen with rabeprazole or placebo. The study was approved by HSC at KUMC and conducted in 21 asymptomatic, H. pylori-negative volunteers in a double-blind, placebo-controlled, crossover design. The content of gastric mucus in GJ, after exhaustive dialysis and complete lyophilization, was assessed gravimetrically, whereas the content of mucin was measured after its purification with equilibrium density-gradient ultracentrifugation in CsC1. Gastric mucus secretion during administration of naproxen with placebo declined significantly both in basal (by 44%; P < 0.001) and in pentagastrin-stimulated (by 35%; P < 0.001) conditions. Coadministration of rabeprazole significantly restored the naproxen-induced impairment in mucus production in basal conditions (by 47%; P < 0.01) and by 22% during stimulation with pentagastrin. Gastric mucin secretion during naproxen/placebo administration also declined significantly in both basal (by 39%; P < 0.01) and stimulated (by 49%; P = 0.003) conditions. Rabeprazole also significantly restored the naproxen-induced decline of gastric mucin output during pentagastrin-stimulated conditions (by 67%; P = 0.003) and by 40% in basal conditions (P = 0.05). The restorative capacity of rabeprazole on the quantitative impairment of gastric mucus and mucin during administration of naproxen may translate into a clinical benefit of protection of the upper alimentary tract from NSAID-related mucosal injury.