Parietal cell mass after short and long term cimetidine treatment of duodenal ulcer.

The parietal cell mass (PCM) was evaluated on endoscopically obtained biopsy specimens of fundus mucosa from 20 duodenal ulcer patients before and after cimetidine treatment. Patients were given cimetidine, 1 g/day, for 28 days. Six out of the 18 cases which healed after short-term therapy went on taking 400 mg/day of cimetidine for 9 months. The PCM was expressed by means of an index (PI) obtained by multiplying the mean cell number per mm of section surface by the mean parenchymal thickness. The analysis of the obtained data failed to demonstrate any significant difference between the PI observed before and after 28 days treatment with cimetidine, while after long term treatment for 9 months, a significant increase of the PI was achieved.