新生鼠缺氧缺血性脑损伤海马区内源性神经干细胞表达及雌激素对其影响的研究  

Study on the proliferation of endogenous neural stem cells in hippocampus of newborn SD rats with hypoxic-ischemic brain damage and the regulation by estrogen

作　　者：金冬梅[1] 姚裕家[1] 

机构地区：[1]四川大学华西第二医院儿科,四川成都610041

出　　处：《四川医学》2008年第9期1111-1113,共3页Sichuan Medical Journal

基　　金：教育部博士点基金项目(20050610071)

摘　　要：目的观察新生鼠缺氧缺血性脑损伤(HIBD)海马区内源性神经干细胞的表达,研究雌激素对HIBD海马区内源性神经干细胞表达的影响。方法本研究将7日龄SD大鼠随机分组(n=8),取HIBD后12h、1、3、7d和14d为观察点,设立5个时间点的模型组和对照组(即假手术组)。采用免疫荧光法检测各时间点海马区的巢蛋白(nestin)表达。雌激素干预实验设立对照组(C3组)、HIBD组(M3组)、空白溶剂组(N3组)及不同剂量17β-雌二醇组[10μg/(kg.d)(L3组)、100μg/(kg.d)(B3组)及1000μg/(kg.d)(H3组)]。使用雌激素各组分别在大鼠HIBD造模后3d,每天颈部皮下注射17β-雌二醇(17-βestradiol,E2)1次,连续3d,空白溶剂组(N3组)在HIBD后注射等量溶剂橄榄油。对所有实验动物腹腔注射5-溴脱氧尿苷嘧啶50mg/kg,2次/d,共3d。结果HIBD后各组与对照组比较,海马区nestin表达在HIBD后1d开始升高,HIBD后3d达高峰,HIBD后7d仍高于对照组(P<0.05)。17-βE2干预各组(L3、B3及H3组)海马区Brdu阳性细胞数较对照组(C3组)明显增加(P<0.05)。干预组随17-βE2剂量增加,海马区Brdu阳性细胞数增加(P<0.05)。结论新生鼠HIBD后,海马区神经干细胞有激活反应,HIBD后3d最明显;雌激素可以促进HIBD后海马区神经干细胞的增殖。Objective To investigate the expression tevels of endogenous neural stem cells（NSCs） marker-nestin in SD rat HIBD model and＇ the control groups. To study the influence of 17β-estradiol（17β-E2） on the proliferation of endogenous NSCs in hippocampus. Methods 7-day-old SD newborn rats were randomly divided into HIBD and the control groups（ n = 8） . The rats were sacrificed at different given time points at 12h, 1,3.7,14d after HIBD respectively .The expression levels of nestin were determined by using immunofluorescence. For estrogen interventional experiment, 3d after HIBD model was chosen as the observing point. 17β-estradiol （ E2 ） with different concentrations （ 10μg/（kg·d）, 100μg/（ kg·d）, 1000μg/（ kg·d ） were daily injected into the rat＇s neck subcutaneously for a total of 3 days. Bromode-oxyuridine（ Brdu ,50mg/kg, twice a day）was intraperitoneally administered to all the rats for 3 days. Cell proliferation（ Brdu-positlve nuclei ） was observed by immunofluorescence staining. Results Nestin expression increased at HIBD 1 d, reached a peak at HIBD 3d,decreased gradually at HIBD 7d compared with the control group（ P 〈 0.05） in hippocampus. Brdu-positive cells increased accordingly with the increase of estrogen＇s concentration. Brdu-positive cells reached a peak in high E2 group（ H3 ）. Brdu-positive cells were significantly different among each group（ P 〈 0.05 ）. Conclusion HIBD can activate NSCs, nestin expression in hippocampus reached a peak at HIBD 3d and decreased gradually then. 17β-E2 has some protective effects on HIBD of neonatal rats. Estrogen could increase the number of Brdu-positive cells in hippecampus.

关 键 词：新生鼠 HIBD 神经干细胞 雌激素 增殖 

分 类 号：R722.1[医药卫生—儿科]