【摘要】 [目的]探讨全脑缺血预处理对再灌注海马区NO含量和Bcl-2表达的影响。[方法]将72只Wistar大鼠随机分为假手术组、脑缺血组和脑缺血预处理组。假手术组:仅暴露4条血管。脑缺血组:四动脉阻断法,全脑缺血10 min。脑缺血预处理组:全脑缺血预处理3 min,再灌注24 h后再次全脑缺血10 min。所有动物均于末次脑缺血再灌注后12、24、48和72 h取脑组织海马区,硝酸还原酶法检测NO2./NO3.含量,间接反应NO含量;免疫组化方法测定海马区Bcl-2表达。[结果]与假手术比较,脑缺血组和脑缺血预处理组NO含量明显增加,脑缺血组NO含量在48 h达到高峰,72 h出现回落;脑缺血预处理组NO含量在各时间点的变化趋势不明显,与脑缺血组在48和72 h比较差异性有显著性意义(P<0.05,P<0.01)。脑缺血组和脑缺血预处理组Bcl-2表达与假手术组比较明显升高;脑缺血组Bcl-2表达24 h达到高峰,48 h开始减少;脑缺血预处理组Bcl-2表达在12 h表达开始增加,48 h达到高峰,72 h开始减少;在48和72 h,脑缺血预处理组Bcl-2表达明显高于脑缺血组(P<0.05,P<0.01)。[结论]脑缺血预处理引起的NO含量增加,可能与Bcl-2上调表达增加及高峰延迟具有一定相关性。更多还原

【Abstract】 [Objective] To observe the effects of global cerebral ischemic precondition on NO content and Bcl-2 expression in the reperfusion of the hippocampus.[Methods] Seventy-two rats were randomly divided into three groups.The rats sham-operated were only explored four vessels,and global ischemia was induced by occluding four vessels for 10 minutes.In ischemic precondition group,the rats firstly subjected 3-min global ischemia and then after 24 hours,repeated ischemia sustained for 10 minutes.At 12,24,48 and 72 h after reperfusion,the hippocampus was removed.The NO content and Bcl-2 expression of hippocampus were respectively measured by the method of nitrate reductase and immunohistochemistry.[Results] Comparing with sham-operated group,NO content enhanced in global ischemic or ischemia precondition group.In ischemic group,the NO content remarkably increased in 48 h and decreased in 72 h,and was significant higher at 48 h and 72 h comparing with ischemic precondition group(P<0.05,P<0.01).The expressions of Bcl-2 in global ischemic and ischemia precondition groups were higher than sham-operated group.In ischemic group,Bcl-2 expression was remarkably increasing at 24 h and decreasing at 48 h(P<0.05,P<0.01),but in ischemic precondition group,it increased at 48 h and decreased at 72 h.Bcl-2 expression was significant lower in ischemic group than that in ischemic precondition group at 48 h and 72 h(P<0.05;P<0.01).[Conclusion] In some extent,the increase of NO content may be related with up-regulated expression of Bcl-2 and delayed peak level in ischemic precondition.更多还原