Rhein restrains the inflammatory response in murine gastric mucosa. (A-E). ELISA for assessing concentrations of proinflammatory cytokines (TNF-α, COX-2, IL-6, and IL-1β) in murine gastric mucosa and PGE2 in murine serum. *P < .05, ***P < .001. ELISA, enzyme-linked immunosorbent assay; IL, interleukin; TNF- α, tumor necrosis factor-alpha; COX-2, cyclooxygenase-2; PGE2, prostaglandin E2.