Effect of Gefarnate on Endogenous Prostaglandin E 2 and Thromboxane in Water-Immersed Rats Prostacyclin

KOBAYASHI, K., ARAKAWA, T., NAKAMURA, H., CHONO, S., YAMADA, H., SATOH, H, and ONo, T. Effect o f Gefarnate on Endogenous Prostacyclin, Prostaglandin E2 and Thromboxane in Water-Immersed Rats. Tohoku J. exp. Med., 1983, 140 (2), 181-185 The level of endogenous prostacyclin (PGI2), prostaglandin E2 (PGE2) and thromboxane A2 (TXA2) in rat gastric mucosa was determined by radioimmunoassay to examine whether gefarnate, an antiulcer agent, maintained the endogenous prostaglandin (PG) level in rats subjected to waterimmersion stress. Seven-hr immersion induced gastric lesions and a marked reduction in PGI2 and PGE2. When gefarnate was injected subcutaneously before stress exposure, the mean ulcer index was reduced and the PGI2 and PGE2 levels were maintained. Our results suggest that the reduction of endogenous PGI2 and PGE2 is a major factor in water-immersion-induced ulcers in rats, and that gefarnate inhibits this ulcer formation by inhibiting a reduction in those PGs induced by water-immersion stress prostacyclin (PGI2); prostaglandin E2 (PGE2); thromboxane A2 (TXA2); gefarnate; gastric mucosa