Partial prevention of ethanol damage of human gastroduodenal mucosa by prostaglandin E2 in vitro.

Biopsies were taken endoscopically from the fundic, antral, and upper duodenal region of healthy volunteers and gastric ulcer patients and were incubated in carbogen-saturated and buffered Medium 199 at 37 degrees C. The rate of DNA synthesis, estimated as incorporation of tritiated thymidine into tissue DNA, was determined as an index of cellular integrity. During the 30-min incubation, ethanol (25% v/v) significantly (p less than 0.01) depressed DNA synthesis by about 50% in the gastroduodenal mucosa of normal subjects and even by two thirds in the gastric mucosa of gastric ulcer patients. Prostaglandin E2 (PGE2) by itself (1 mg/50 ml) had no stimulatory effect on DNA synthesis; it did, however, reduce the drastic fall in DNA synthesis due to ethanol (p less than 0.005) when administered concomitantly. The basic process underlying cytoprotection by PGE2 in vitro remains to be elucidated. Some indirect mechanisms, such as stimulation of gastric mucosal blood flow, are ruled out by these experiments.