Abstract: Objective To explore the expression of trefoil factor 2(TFF2) in submaxillary glands during the self healing of experimental gastric ulcer in rats. Methods Totally 48 male SD rats were randomly divided into gastric ulcer group(EM>n/EM>=42)and normal group(EM>n/EM>=6). The expression of TFF2 peptide and TFF2 gene were detected by the methods of immunohistochemistry and RT-PCR respectively in the gastric ulcer group and normal group. Results TFF2 immunoreactive cells were mainly located in the cytoplasm of the epithelial cells in the ducts,such as intercalated duct,striated ducts, interlobular duct, and which also showed positive expression in the cavity,even near the cavosurface. TFF2 peptide also showed strong expression in few granule cells or in those cells without granules, and which were weakly positive or negative in the cells with many granules.The integral absorbance values(IEM>A/EM>) and area density(AD) values obviously increased on the day 1 after gastric ulcer(EM>P/EM><0.01),and which was the lowest on the day 2 (EM>P/EM>>0.05),then gradually increased again on the day 4 and day 6 (EM>P/EM><0.01) ,and kept on a high level till 10 days to 23 days compared with the normal group(EM>P/EM><005). The IEM>A/EM> of TFF2/GAPDH in 1,4,6,10,14 and 23 days gastric ulcer group were obviously higher than that of the normal group except the 2\|day gastric ulcer group（EM>P/EM><0.01 or EM>P/EM><0.05）. Conclusion TFF2 in rat submaxillary glands may participate in the regulation of self healing in gastric ulcer.

Key words: Gastric ulcer, Trefoil factor 2, Submaxillary gland, Immunohistochemistry, RT-PCR, Rat