Protection of Isolated Rat Gastric Cells by Prostaglandins from Damage Caused by Ethanol. Preliminary Report

The direct effects of exogenous and endogenous prostaglandins (PGs) on damage to isolated gastric cells caused by ethanol were assessed in rats. 16,16-Dimethyl-PGE2 (dmPGE2) significantly inhibited cellular damage caused by 15% ethanol in three fractions rich in surface epithelial cells, rich in parietal cells, and rich in chief cells at the concentration of 10(-6) M but it was less effective either at a lower concentration (10(-7) M) or a higher concentration (10(-5) M). The surface epithelial cells synthesized 6-keto-PGF1 alpha and thromboxane (TX) B2 predominantly, and less PGE2. Indomethacin completely inhibited synthesis of these prostanoids. This agent induced cellular damage in a dose-related way and this damage was inhibited by 10(-6) M dmPGE2. Indomethacin alone at the dose of 10(-4) M, at which synthesis of prostanoids was completely inhibited, did not affect the viability of the cells, but made the cells susceptible to damage caused by 15% ethanol. This effect of a minimum dose of indomethacin was inhibited by 10(-6) M dmPGE2. These results suggest that dmPGE2 has a direct protective effect on the isolated gastric cells in rats, and this effect is not limited to a specific cell type. That endogenous prostanoids have a possible role in the maintenance of cellular integrity is also postulated.