Background Adult stem cells provide a promising alternative for the treatment of injured tissues.We aimed to investigate the effect of in vivo transplantation of bone marrow mesenchymal stem cells (BMMSCs) on injured gastric mucosa in rats.Methods The gastric ulcer in rats was induced by indomethacin.BMMSCs from male rats,labeled with the fluorescent cell linker 5,6-carboxyfluorescein diacetate succinimidyl ester (CFDA SE),were transplanted into the female rats via tail vein injection.The healing process of gastric ulcers was monitored by HE staining.The protein levels of vascular endothelial growth factor (VEGF) and the epidermal growth factor receptor (EGFR) in the injured gastric mucosa were determined by immunohistochemistry.Results At 48 and 72 hours after BMMSCs transplantation,the CFDA SE labeled cells were found scattered in the injured gastric mucosa,but not in the gastric mucosa of control rats.At 72 hours after BMMSCs transplantation,the mean ulcer index was 12.67±2.16 in the BMMSCs transplanted group and 17.33±1.97 in vehicle-treated controls (P ＜0.01).Both VEGF and EGFR protein expression levels were significantly higher in the gastric section from the rats that received BMMSCs transplantation as compared to rats without BMMSCs transplantation.Conclusion Autologous BMMSCs transplantation can accelerate gastric ulcer healing in injured gastric mucosa in a rodent model.