Duodenal and antral mucosal prostaglandin E2 synthesis in a study of normal subjects and all stages of duodenal ulcer disease treated by H2 receptor antagonists

Abstract

We tested the hypothesis that the production of prostaglandin E2 (PGE2) is impaired in duodenal ulcer disease and affected by treatment and healing. This was investigated by a study of maximal PGE2 synthesis rates in duodenal and antral mucosal biopsies obtained at endoscopy. The patients were divided into three groups. Group (a): endoscopically normal controls (n = 56); group (b): treatment controls (non-DU disease: gastric ulcer or oesophagitis treated by histamine H2 receptor antagonists) (n = 41); and group (c): patients with DU disease (n = 183) further subdivided into group (c1) active ulcer not on treatment (n = 47), (c2) treated active ulcer (n = 35), (c3) healed ulcer on treatment (n = 86), and (c4) healed ulcer not on treatment (n = 15). Group (a) synthesised (mean (SD] 106.6 (39.0) pg PGE2/mg wt of tissue from the duodenal bulb and 129.9 (56.9) from the second part of the duodenum. No difference was found between group (a) and (b) at either site. Group (c1) ulcer rim made 49.8 (22.7) and at all stages ulcer rim and scar made less than the control duodenal bulb (p less than 0.02). Uninvolved duodenal bulb form groups (c1) (63.4 (31.0], (c2) (83.6 (38.5], and (c3) (81.5 (31.1], however, also made significantly less than controls (p less than 0.02) and a similar though non-significant trend was seen in group (c4). Biopsies from the second part of the duodenum did not synthesise significantly less than the control group but a similar trend was noticed at each stage of ulcer treatment. Biopsies of control antrum synthesised 124.5 (32.2) but only 93.7 (44.2) in group (cl) (p < 0.005). All stages of duodenal ulcer healing were associated with a decreased capacity to synthesise the major prostaglandin PGE2 at the ulcer site and the uninvolved duodenal bulb and, in acute untreated duodenal ulcer, the uninvolved antrum. This decreased capacity may be the consequence of the disease process itself and not secondary to the treatment, indicating a basic pathophysiological abnormality which may explain the characteristic tendency of the disease to relapse.