Interactions among gastric somatostatin, interleukin-8 and mucosal inflammation in Helicobacter pylori-positive peptic ulcer patients

Background. To investigate whether Helicobacter pylori infection, but not d rugs, affects gastric somatostatin, interleukin-8 (IL-8), histological infl ammation through eradication therapy, and interactions among these paramete rs. Methods. Twenty-eight H. pylori-positive patients (21 males; mean age 47.0 years) with either gastric ulcer(GU: n = 11) or duodenal ulcer (n = 17)diag nosed endoscopically were treated with dual therapy. Eradication was define d as negative microbiologic tests and C-13-urea breath test. Levels of antr al and gastric juice somatostatin and mucosal IL-8 were measured by radioim munoassay and enzyme-linked immunosorbent assay, respectively Histology was assessed by the Sydney system. Results. H. pylori was eradicated in 15 patients (10 males, 6 GU) out of 28 (54%). The patients' backgrounds did not affect the eradication of H. pylo ri. Successes in eradication significantly increased antral and juice somat ostatin contents, and dramatically decreased IL-8 levels and histological g astritis. In contrast, persistent H. pylori infection did nor affect somato statin and histological gastritis. An inverse correlation was present betwe en changes in somatostatin levels and histological activity. No relationshi p was observed in changed values between antral somatostatin and IL-8. Conclusions. These results indicate that eradication of H. pylori, but not the drugs used, induced an increase in somatostatin levels in the antrum an d gastric juice, suggesting a close relationship between N. pylori and gast ric somatostatin regulation. A close correlation between an increase in gas tric somatostatin levels and the normalization of histological activity was present, suggesting that certain peptide-immune interactions in the gastri c mucosa exist in N. pylori infection.