The effect of prostacyclin on the gastric mucosa in portal-hypertensive rats.

Background/aims: This study investigates the effect of prostacyclin, which is thought to be involved in the hemodynamic circulation, on the gastric mucosa of rats with portal hypertension.

Methodology: Various gastric functions were evaluated in portal vein ligated rats after the intraperitoneal administration of either a placebo or prostacyclin for 7 days.

Results: The gastric mucosal damage induced by the instillation of 90% ethanol was significantly greater in the prostacyclin-treated group than in placebo-treated group. The portal pressure was similar in both groups. There was no significant difference between the two groups in plasma concentration of 6-keto-PGF1a (a stable metabolite of prostacyclin), whereas the mucosal content of 6-keto-PGF1a was significantly higher in the prostacyclin-treated group than in the placebo-treated group. Prostacyclin pretreatment significantly increased the gastric mucosal blood flow, estimated by laser-Doppler flowmetry, and the hemoglobin content of the gastric mucosa, measured by reflectance spectrophotometry, whereas the oxygen content remained unchanged.

Conclusions: We speculate that the increased gastric mucosal perfusion induced by a high content of prostacyclin in the portal hypertensive gastric mucosa may play a role in the pathogenesis of ethanol-induced gastric mucosal damage.