Changes in rat gastric mucosal glycoproteins in portal hypertension

The aim of this study was to determine the effect of portal hypertension (PHT) on gastric mucosal glycoproteins in rats. PHT was induced experimentally by partial ligation of the portal vein (PVL) in 20 male Wistar rats: 10 rats (PVL4 group) were analyzed after 4 weeks and the remaining 10 (PVL8 group) after 8 weeks. In another group of 10 rats (control group), sham operations were performed. The severity of gastric mucosal lesions was evaluated macroscopically by a gross ulcer index. The gross ulcer indices in the PVL groups were significantly higher than those in the controls (p < 0.05). Histomorphometric evaluation of the intraepithelial mucin content, with the periodic acid-Schiff-Alcian blue staining technique, confirmed a significant decrease in mucosal glycoprotein production in the PVL groups (p < 0.05). Quantitative changes in gastric mucosal hexosamines were also used for mucosal glycoprotein analyses, and the hexosamine content of the gastric mucosa in the control, PVL4 and PVL8 groups were 300.7 +/- 7.8, 177.2 +/- 4.9 and 169.1 +/- 3.5 micrograms/100 mg dried mucosa, respectively. The gastric mucosal hexosamine content was significantly lower in the PVL groups than in the control group (p < 0.05). No significant differences were observed between the two PVL groups in the above-studied parameters. These findings reveal that PHT causes a decrease in gastric mucosal glycoproteins in rats, and the decreased mucin content may weaken an important defensive factor of gastric mucosa. We suggest that gastric mucosal glycoproteins may play an important role in the pathogenesis of gastric mucosal lesions from PHT.