THE EFFECT OF PORTAL-HYPERTENSION ON GASTRIC EPITHELIAL PROLIFERATIONIN RATS

We investigated the effect of portal hypertension over time on gastric epithelial proliferation in rats. Portal-vein, ligation (PVL) was app lied to fourteen Wistar rats to produce experimental portal hypertensi on: seven rats (PVL2) had histological analysis after 2 months and the remaining seven (PVL4) after 4. An additional group of seven was empl oyed as a control. Each rat was injected with bromodeoxyuridine and ki lled an hour later to assess gastric epithelial proliferation by an im munohistochemical staining technique. The labeling index between PVL a nd 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 corre sponding 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 signi ficantly different between the control and PVL rats. In the PVL2 group , the frequency distribution of labeled cells showed a shift toward th e mucosal surface in fundic glands. No significant differences between the two PVL groups were observed in any of the studied parameters. Th is study suggests that portal hypertension may inhibit gastric epithel ial proliferation in rats.