The gastric mucosa in experimental duodenogastric reflux. A scanning electron microscope study

In the course of a long-lasting experiment on entero-gastric reflux in the dog, we examined with the SEM the gastric mucosal surface epithelium in 22 animals chronically exposed to any type of enteral diversion to the stomach, associated in one group to a highly selective vagotomy. Tissue samples were collected at the time of corrective surgery and at sacrifice in the survivors. The control group was composed of 4 dogs with Roux-en-Y loops. At remedial surgery, about half the dogs failed to display any cellular alteration, regardless of the group they belonged to. The isolated biliary reflux group alone showed fundic erosions in 100% of the dogs. In the antral area, the isolated pancreatic reflux appeared to be the most damaging. Similar erosions were found in the antrum and the fundus of the majority of control dogs. Six to twelve months after suppression of the reflux, the erosions showed a tendency to incomplete regression, and more often to progression. We advocate the protective role of the chronic alkaline reflux on the gastric mucosa to explain our results.