Clot lysis by gastric juice: an in vitro study.

Gastric juice from patients with peptic ulcer disease and from patients with no upper gastrointestinal abnormality was studied in order to assess its effect on a formed fibrin clot. In both groups of patients gastric juice caused a marked increase in fibrinolysis as evidenced by a shortening of the euglobulin clot lysis time. This plasmin mediated fibrinolytic activity was found to be heat labile and only present in an acid environment. Addition of tranexamic acid or sucralfate to gastric juice almost completely reversed this effect, whereas pepstatin was only partially effective. It is probable that acid dependent proteases other than pepsin are responsible for the marked fibrinolysis. The ulcer healing agent sucralfate might be useful in those patients at risk of bleeding or rebleeding from active peptic ulcer disease.