Further Studies on the Inhibition of Pepsin by Bile Salts

A higher incidence of peptic ulceration has been reported in patients recovering from operations that divert bile from the duodenum. Previous studies have shown that hydroxylated bile salts inhibit the proteolytic activity of pepsin, an integral agent in the production of peptic ulcer. In this study, the pepsin inhibitory activity of 16 bile salts (6 unconjugated, 5 glycoconjugated, and 5 tauroconjugated bile salts), including bile salts with no hydroxyl groups, was tested in vitro. All bile salts inhibited pepsin proteolytic activity and the degree of pepsin inhibition increased in proportion to their concentrations. The range of maximal inhibition was 90-73% for unconjugated bile salts; 74-35% for glycoconjugated bile salts; and 71-46% for tauroconjugated bile salts. These findings support the need for clinical studies to evaluate administration of bile acids to bile-diverted patients.