Involvement of Endothelin-1 in Up-regulation of Gastric Mucosal Inflammatory Responses toHelicobacter pyloriLipopolysaccharide

Abstract

In this study, we investigated gastric mucosal inflammatory responses duringHelicobacter pylorilipopolysaccharide-induced gastritis by analyzing the interplay between mucosal expression of endothelin-1 (ET-1), interleukin-4 (IL-4) and tumor necrosis factor-α (TNF-α). The assays conducted 4 days after intragastric dose ofH. pylorilipopolysaccharide demonstrated a pattern of acute mucosal reaction characterized by the inflammatory infiltration of the lamina propria, hyperemia, and epithelial hemorrhage. This was accompanied by a 3.1-fold increase in the mucosal expression of ET-1 and a 9-fold enhancement in TNF-α, while the level of IL-4 showed a 20.8% decline. The results implicate ET-1 in gastric mucosal responses toH. pylori,and suggest that an increase in its level, combined with a loss of compensatory action by IL-4, may be responsible for the induction of TNF-α and triggering apoptotic events that exacerbate the inflammatory process.