The microscopic observation of Bax protein appearance (A–E) and quantitative analysis (F) of Bax protein expression in rats. A and F, normal controls had normal stomach tissue layers and very reduced Bax protein intensity; B and F, ulcer controls experienced severe stomach tissue injury and an increase in the Bax protein expressions; C and F, omeprazole-treated rats had mild gastric mucosal injury and reduced Bax protein compared to ulcer controls; D and E, rats pre-supplemented with REPP (250 and 500 mg/kg) rats had moderate gastric tissue damage and a decrease in the Bax protein expression (Bax stain, magnification 20×). REPP treatment caused a down-regulation of a pro-apoptotic Bax protein that prevented further gastric tissue damage. ns, non-significant; *, p < 0.05; ****, p < 0.0001.