The effect of portal hypertension on gastric epithelial proliferation in rats.

We investigated the effect of portal hypertension over time on gastric epithelial proliferation in rats. Portal-vein ligation (PVL) was applied to fourteen Wistar rats to produce experimental portal hypertension: seven rats (PVL2) had histological analysis after 2 months and the remaining seven (PVL4) after 4. An additional group of seven was employed as a control. Each rat was injected with bromodeoxyuridine and killed an hour later to assess gastric epithelial proliferation by an immunohistochemical staining technique. The labeling index between PVL and control animals differed significantly (p < 0.05). Labeling indices in fundic mucosa were 5.7 +/- 0.2% in controls, 3.9 +/- 0.3% in PVL2 rats and 4.0 +/- 0.3% in PVL4 rats, while in antral mucosa the corresponding figures were 7.5 +/- 0.6, 4.6 +/- 0.3 and 4.0 +/- 0.3%. In neither fundic nor antral mucosa was the total mucosal thickness significantly different between the control and PVL rats. In the PVL2 group, the frequency distribution of labeled cells showed a shift toward the mucosal surface in fundic glands. No significant differences between the two PVL groups were observed in any of the studied parameters. This study suggests that portal hypertension may inhibit gastric epithelial proliferation in rats.