Injury to the gastric mucosa and cellular dynamics in a rat model of duodenogastric reflux: The possible significance of gastrin induction and a heatshock protein

Injury to the gastric mucosa caused by duodenogastric reflux (DGR) is often encountered after gastrectomy or truncal vagotomy (V) with pyloroplasty. T his study was designed to investigate the histological features of the gast ric mucosa under such conditions. A rat model of DGR and DGR+V was establis hed and the thickness of the oxyntic mucosa was measured. Cellular dynamics in the presence of injury to the gastric mucosa caused by DGR were investi gated by the immunohistochemical staining of bromodeoxyuridine (BrdU) and h eat shock protein 70 (HSP70). The relationship between persistent hypergast rinemia and mucosal injury was also studied. Duodenogastric reflux activate d the intracellular induction of HSP70 in our rat model of DGR. Hypergastri nemia was noted in the V group. Compared with values from the DGR group, th e numbers of BrdU-labeled cells increased, the glandular proliferation zone expanded, and the thickness of the oxyntic mucosa was significantly higher in the DGR+V group. Compared with the DGR group, there was greater inducti on of HSP in the DGR+V group during the acute stage. This finding suggests that denervation of the gastric mucosa and hypergastrinemia after vagotomy may be associated with the expression of HSP.