Determination of prostaglandins and the effect of indomethacin on rat gastric mucosa.

Prostaglandins protect the gastrointestinal mucosa against various ulcerogens. There are only a few reports about endogenous prostaglandins in the gastric mucosa. We present a method for determining mucosal prostaglandins and an investigation on the effect of indomethacin on prostaglandin E2 levels in the rat gastric mucosa. The levels of prostaglandins B, E1, E2, and F were higher in the antral mucosa (311 +/- 123, 632 +/- 147, 2099 +/- 455, and 415 +/- 115 ng/g, respectively) than in the fundic mucosa (33 +/- 2, 202 +/- 38, 914 +/- 229 and 138 +/- 22 ng/g, respectively). In both mucosal tissues, the prostaglandin E2 level was the highest and it was markedly reduced with indomethacin in a dose-related manner. The difference in the mucosal levels of prostaglandins suggests that in rats, mucosal damage occurs mainly in the fundus. The observed marked reduction of mucosal prostaglandin E2 following the administration of indomethacin may aid in elucidating the pathogenesis of gastric mucosal lesions induced by these types of agents.