Ultrastructure of duodenal epithelial cells in patients with active duodenal ulcers and after treatment with cimetidine.

Comparative ultrastructural studies were conducted on biopsy specimens taken under direct vision by endoscopy from the normal duodenum, from the edge of deep and flat duodenal ulcers, and from areas 1 cm away from such ulcers. In addition, the ultrastructure of biopsy tissue from the scar of ulcers which healed after 6 weeks' therapy with the histaminastructural studies of tissue form the edge of both flat and deep duodenal ulcers showed gross pathological changes, particularly with regard to microvilli. Cells from the edge of deep ulcers showed increased secretory activity. Epithelial tissue 1 cm from flat duodenal ulcers exhibited ultrastructural changes far more severe than cells 1 cm from deep duodenal ulcers. The epithelial tissue from the scar area after 6 weeks' treatment appeared capable of regaining a fully functional role, although it was not normal in all specimens.