脑红蛋白在大鼠局灶性脑组织中的保护作用

目的观察局灶性脑缺血后缺血半暗区脑红蛋白（neuroglobin,NGB）表达和其脑保护作用,阐明NGB在局灶性脑缺血中是否能延长缺血半暗区神经元的存活。方法大鼠随机分为假手术组（sham）（n=6）、缺血组（CI）、干预组（IV）。CI制作MCAO模型后按断头时程分为5min、0.5h、1h、6h、24h、72h六个亚组（n=6）。IV将单克隆NGB抗体（MoAb-NGB）注入左侧尾壳核30min后制作MCAO模型,分为0.5h、1h、6h、24h、72h五个亚组（n=6）,sham于24h断头。取两侧大脑作HE和NGB免疫组化染色观察左右两侧大脑NGB表达和梗死体积。结果左侧大脑缺血5minNGB表达明显上升,0.5h达高峰,随后下降,6h接近正常;而右侧大脑相应区域NGB表达未见明显表达。结论脑缺血后NGB在缺血半暗区早期升高,然后逐步下降,于6h降至正常,能减少梗死面积,具有脑保护作用。

Expression of Neuroglobin and Neuroprotective Mechanisms after MACO in Rat

Objective To research the regularity of expression of NGB in focal cerebral ischemia and its roles of neuropretection,provide the theory that whether NGB can prolong the survival time of neuron in ischemia penumbra.Methods We classified the male SD rats into sham operation group、cerebral ischemia groups（CI）、intervention groups（IV） in random,After MCAO model made rats were killed at different time and classified into 5min、0.5h、1h、6h、24h、72h defferent subgroups（n=6） in CI.In IV,we injected the MoAb-NGB into left striatum ,and a half hour later producing the model of MCAO ,then rats were killed at different time and classified into 0.5h,lh,6h,24h,72h defferent subgroups（ n =6） , then specimens were made in corresponding. Results Compared with sham operation group, the expression of NGB ascended obviously in ischemia penumbra at beginning of ischemia（ P 〈0. 01 ） ,peaked at 0. 5h（ P 〈0. 01 ） and descended thereafter, it closed to sham opera- tion group after 6h. Compared with subgroup each among the groups of CI,there was significant difference（ P 〈0.01 ）, otherwise there are no expression in the right corresponding region. Conclusion The expression of NGB ascends early in ischemia penumbra after focal ischemia was produced, then descends gradually and to normal level at 6h. NGB can reduce the volume of ischemia after MCAO in rat is produced. This ascertain that NGB play the role of neuroprection.