Tahoora Shomali
Mahdi Raeesi
Narges Eskandari-Roozbahani

Introduction: The present study investigated protective effect of Zataria multiflora essential oil on ethanol-induced gastric ulcer in rats along with its possible mechanism(s).Methods: Eighty male adult rats were randomly allocated into ۸ groups as follows: ۱: negative control (NC); ۲, ۳ and ۴: positive control (PC, distilled water), vehicle control (VC, corn oil) and comparative control (CC, omeprazole ۲۰ mg/kg in distilled water), respectively; ۵, ۶, ۷ and ۸: treated with ۱۰۰, ۲۰۰, ۴۰۰ and ۸۰۰ μL/kg Z. multiflora essential oil. After ۱ hour, gastric ulcer was induced by ۴ mL/kg ۷۵% ethanol orally to rats of groups ۲-۸. One hour later, blood samples were collected and then all rats were sacrificed and their stomachs were immediately removed.Results: In PC and VC groups severe lesions were observed in stomachs where mucosal lesions in CC group as well as groups treated with Z. multiflora essential oil (especially higher doses) were very mild with regard to ulcer area and number. No significant difference was observed in mucosal prostaglandin E۲ (PGE۲) and serum tumor necrosis factor-α (TNF-α) level among groups, gastric mucosal nitric oxide (NO) content was significantly higher in rats treated with Z. multiflora essential oil at ۲۰۰, ۴۰۰ and ۸۰۰ μL/kg as compared to PC group. Rats in CC, Z. multiflora ۴۰۰ and Z. multiflora ۸۰۰ groups showed higher mucosal total antioxidant capacity (TAC) as compared to PC group.Conclusion: Z. multiflora essential oil has a gastro-protective effect against ethanol-induced gastric ulcer in rats which is probably due to its antioxidant and NO production enhancing effect.