茶多酚对胃黏膜缺血再灌注损伤的保护作用

目的 观察茶多酚(polyphenols of tea,PPT)对因胃缺血致胃黏膜损伤的保护作用.方法 将35只雄性SD大鼠随机分成7组A空白对照组;B假手术组;C手术组;D 20 mg/kg PPT组;E 40 mg/kg PPT组;F 80 mg/kg PPT组;G 160 mg/kg PPT组.在成功制作胃缺血动物模型的基础上,观察大鼠胃缺血30 min再灌注后1 h,2 h,6 h,12 h大鼠血浆中超氧物歧化酶(SOD)、丙二醛(MDA)水平的变化,同步观察再灌注12 h后胃黏膜内毛细血管内皮中血管内皮生长因子(VEGF)和CD34的表达变化.并设立手术组、假手术组以及空白对照组予以对照.结果 各模型组相应时间点的SOD含量明显高于手术组、假手术组和空白对照组(P＜0.05),其中40 mg/kg组最为显著(P＜0.01);20 mg/kg,40 mg/kg,80 mg/kg组相应时间点的MDA含量明显低于手术组、假手术组和空白对照组(P＜0.05),其中80 mg/kg组最为显著(P＜0.01),160 mg/kg组则略低于手术组、高于假手术组和空白对照组(P＞0.05);各模型组的胃黏膜内毛细血管内皮中CD34表达水平明显高于手术组(P＜0.05),略低于假手术组和空白对照组(P＞0.05);各模型组的胃黏膜内毛细血管内皮中VEGF表达水平明显低于手术组(P＜0.05),略高于假手术组和空白对照组(P＞0.05).结论 茶多酚对因缺血再灌注导致损伤的胃黏膜具有保护作用.

Protective effect of polyphenols of tea on gastric mucosal injury induced by ischemia reperfusion

Objective To explore protective effect of polyphenols of tea on gastric mucosal injury induced by ischemia reperfusion(IR).Methods Thirty-five adult male Sprague-Dawley(SD) rats were randomly divided into 7 groups: normal control group(Group A),sham operation group(B),operation group(C),PPT groups(D.20 mg/kg,E.40 mg/kg,F.80 mg/kg,G.160 mg/kg,respectively).The gastric ischemia animal model was successfully set up.After ischemia for 30 min,the rats were reperfused and intravenously injected with PPT.The levels of plasma SOD and MDA were measured after reperfusion for 1 h,2 h,6 h,12 h.CD34 and VEGF in epithelial cells of gastric mucosa were measured after 12 h reperfusion. Results SOD levels in PPT groups were significantly higher than in group C,B and A at the same time point(P<0.05),and highest in group E(P<0.01).MDA levels in groups D,E and F were lower significantly than in groups C,B and A at the same time point(P<0.05),and lowest in group F(P<0.01).MOD level in Group G was lower slightly than in group C,but higher than in groups B and A(P>0.05).CD34 expression in epithelial cells of gastric mucosa was significantly higher in PPT groups than in group C(P<0.05),but slightly lower than in groups B and A(P>0.05).VEGF expression in epithelial cells of gastric mucosa was significantly lower in PPT groups than in group C,but slightly higher than in groups B and A(P>0.05).Conclusion Polyphenol of tea can protect the gastric mucosa injury induced by ischemia reperfusion.