Prostacyclin-Induced Gastric Mucosal Vasodilation and Inhibition of Acid Secretion in the Dog

Abstract

Summary

Intraarterial infusion of PGI₂ or PGE₂ causes a dose-dependent inhibition of histamine-stimulated gastric acid secretion in an in vivo-chambered stomach, PGI₂ being less potent inhibitor than PGE₂. While PGE₂ decreases gastric mucosal blood flow, PGI₂ causes a marked and dose-dependent increase in mucosal blood flow. PGI₂ is also secretory inhibitor after intravenous, but not after intraportal administration. 6-Keto-PGF_1α, a breakdown product of PGI₂, has no effect on gastric secretion or gastric mucosal circulation. PGI₂ lowers systemic arterial blood pressure, the effect being more pronounced after intravenous than intraarterial or portal administration. This suggests a marked in-activation of this PG during the liver transit.

This work was supported by Research Grant 10-RMZ-1.