ABSTRACT
Objective To investigate the effects of Celecoxib,a selective COX-2 inhibitor,on the healing of gastric ulcer in rats,and reveal the rale of ERK signal transduction pathway in the mechanism of delaying the healing of gastric ulcer.Methods Forty-eight rats were randomly divided into model group(n=40) and sham operation group(n=8).In the rats in model group acetic acid-induced gastric ulcer was reproduced,while in sham operation group,rats underwent the sham procedure.Eight rats in sham-operation group and eight rats in model group were euthanized three days after the procedure.The other thirty-two rats in model group were divided into two subgroups including Celecoxib group and NS group(n=16).Three days after the procedure,rats in Celecoxib group received a gavage of 0.2% Celecoxib solution,and those in NS group received equal amount of 0.9% NaCl solution.Rats in Celecoxib group and NS group were euthanized on sixth and ninth day after ulcer induction(8 rats at each time point in each group).The effects of Celecoxib on the healing of gastric ulcer were observed.Its effects on the activity of Raf-1 and ERK1/2,and the expression level of two transcription factors c-Fos and c-Jun were also determined by Western blot analysis.Results Nine days after ulcer induction,the ulcer area was 11.9?3.1mm2 and 19.7?3.8mm2 in NS group and Celecoxib group,respectively,and they were much smaller than those on third day(P