Abstract: To screen active sites and investigate the protective effect of Dendrobium officinale Kimura et Migo on aspirin-induced gastric mucosal injury in rats as well as the possible mechanism.Human gastric epithelial cell line GES-1 was cultured in vitro, and pretreated with different concentrations of D.officinale extracts before aspirin treatment;MTS assay was used to detect the cell viability.The content of LDH was also determined by the LDH kit.Gastric mucosal injury models induced by aspirin in SD rats was established by intragastric administration of different doses of D.officinale for seven days,and ulcer area was assessed to analyze the effect of D.officinale on gastric mucosal injury induced by aspirin in rats.The content of gastric secretion,gastric acid,pepsin,NO,TNF-α, IL-6, SOD,MDA and PGE-2 were measured to analyze the mechanism.The results showed that the cell viability of polysaccharide fraction of D.officinale increased significantly.The content of LDH significantly decreased,and other group was not significantly different.Compared with aspirin-treated group,the content of gastric secretion,gastric acid,pepsin and gastric ulcer area of polysaccharide group rats was significantly reduced;Compared with aspirin-treated group,NO,SOD and PGE-2 of polysaccharide group rats was significantly increased,while the content of TNF-α,IL-6,MDA were significantly decreased.In conclusion, D.officinale polysaccharide had a significant anti-acute gastric ulcer effects induced by aspirin.

Key words: Dendrobium officinale Kimura et Migo, GES-1 cells, aspirin, gastric ulcer, polysaccharide