Are tryptase and cathepsin D related to Helicobacter pylori infection and mucosal gastrin in peptic ulcer?
The pathogenesis of peptic ulcer is a complex phenomenon and several factors are thought to be involved in this process. Among others, Helicobacter pylori infection, hypergastrinaemia and some proteases seem to play an essential role in inducing peptic ulceration. We investigated whether tryptase (a serine endoprotease released by mast cells) and cathepsin D (a lysosomal hydrolase which seems able to derange the extracellular matrix) play a part in peptic ulcer disease and whether they are linked to Helicobacter pylori infection and mucosal content of gastrin. We studied 13 controls, 25 patients with gastric ulcer, 47 with duodenal ulcer and 11 with duodenitis. Tryptase and cathepsin D were measured in mucosal biopsy specimens (body and antrum of the stomach and duodenum) using IRMA methods. Gastrin was assayed in the antral mucosa by means of a RIA method. Helicobacter pylori infection was histologically evaluated (Giemsa). Tryptase and cathepsin D levels were higher (25%) in patients