The antral gastrin-producing cells in duodenal ulcer patients. A light microscopic and ultrastructural study during long-term, low dose treatment with cimetidine.

The antral mucosa has been examined in four duodenal ulcer patients before and during long-term, low dose treatment with cimetidine (given a total dose of between 472 g and 894 g). No convincing changes were found in the number or the volume of G cells. Signs of inactivity were demonstrated ultrastructurally, with small granules of intermediate type, a reduced amount of granular endoplasmatic reticulum and Golgi complex, mostly showing no signs of granulogenesis. The occurrence of bundles of cytoplasmic microfilaments, not observed before treatment and the reduced number of D cells may also be signs of inactivity. Hyperplasia and/or neoplasia were not seen in other antral endocrine cells.