ULTRASTRUCTURAL-STUDY OF ANTRAL G-CELL IN PATIENTS WITH DUODENAL-ULCER - EFFECT OF HELICOBACTER-PYLORI ERADICATION

Background. It is established now that Helicobacter pylori infection i s associated with exaggerated gastrin release to meals and other stimu li and that the abnormal secretion of gastrin is reversed after succes sful treat ment of the infection. By comparing morphology of G cells f rom the same patients before and after treatment, we were able to inve stigate the ultrastructural effect of cure of H. pylori on G cells. Me thods. Gastric mucosal biopsy specimens were obtained from 10 patients with duodenal ulcer before and 3, 6, and 9 months after cure of H. py lori infection. Negative controls consisted of four healthy volunteers without H. pylori infection. G cells were evaluated by immunohistoche mical and electron microscopy. Treatment with H-2-antagonists was cont inued for 6 months after cure of the H. pylori infection. Results. Ult rastructural studies of secretory granules of antral G cells in contro ls displayed a broad range of electron density ranging from dark with a full appearance to totally electron-lucent with a ''vacuolating'' ap pearance. In duodenal ulcer patients before treatment, electron-lucent vacuolating granules predominated. After elimination of H. pylori, G- cell granules showed a marked increase in electron density close to th at of controls. Conclusions. Our study showed that the density of gran ules of G cells is decreased in H. pylori-infected duodenal ulcer pati ents compared to that in H. pylori-negative controls and is consistent with enhanced gastrin release. Cure of H. pylori infection was associ ated with return to normal density of G-cell granules.