Effects of prostaglandin E₂ on gastric irritant-induced apoptosis

We previously reported that various gastric irritants induced both apoptosis and necrosis in cultured gastric mucosal cells. In a continuation of this work, the present study has examined the effects of prostaglandin E₂ (PGE₂), a cytoprotective factor for gastric mucosa in vivo, on gastric irritant-induced apoptosis and necrosis in vitro. PGE₂ inhibited ethanol-induced apoptosis and increased cell viability in a dose-dependent manner in primary cultures of guinea pig gastric mucosal cells. PGE₂ also inhibited hydrogen peroxide-induced apoptosis. In contrast, PGE₂ showed no cytoprotective effects against ethanol-induced necrosis. Based on these results, we consider that the cytoprotective effects of PGE₂ on gastric mucosa in vivo can be partially explained by its inhibitory effect on gastric irritant-induced apoptosis.