Cell renewal in non-specific duodenitis, ulcer-related duodenitis and duodenal ulcer. Experiments in Mastomys (Praomys natalensis).

Cell renewal in the duodenal mucosa of Mastomys was studied by autoradiography 1 and 24 h after intraperitoneal injection of tritiated thymidine. Non-specific duodenitis and duodenal ulceration were produced with a continuous infusion of histamine. Mucosal renewal in the duodenum of 30 control Mastomys was compared with 30 which received histamine dihydrochloride for 5 days. No abnormality developed in the controls, but 11 of the experimental group developed non-specific duodenitis and 12 duodenal ulcers. The size of the proliferative zone was increased in the Mastomys sacrificed 1 h after injection of tritiated thymidine which received histamine, compared with controls (p = 0.004). The number of labelled nuclei (p = 0.0003) and the size of the columns of labelled nuclei (p = 0.001) were increased in the Mastomys receiving histamine and sacrificed 24 h after injection of tritiated thymidine, compared with controls. The number of labelled nuclei (p = 0.004) and the size of the columns of labelled nuclei (p = 0.01) were increased in the Mastomys with ulcers compared with the other Mastomys which had received histamine. Cimetidine prevented duodenitis and ulceration, normalising the pattern of cell renewal. There was correlation between the severity of non-specific and ulcer-related duodenitis as judged by Lance's system and the number of labelled nuclei (Spearman rank correlation coefficient 0.771, p less than 0.002). Cell renewal increased as duodenitis became more severe and duodenal ulcers were found in duodenal mucosa where cell renewal was fastest.