脂多糖致感染性脑水肿大鼠星形胶质细胞的活化和凋亡

目的通过观察脂多糖（Lipopolysaccharide，LPS）致大鼠感染性脑水肿后星形胶质细胞的凋亡、活化及iNOS表达情况，探讨在LPS致脑水肿中星形胶质细胞的作用。方法84只雄性SD大鼠，随机分为3组：空白对照纽（C组，n=12）；生理盐水对照纽（S组，n=12）；感染性水肿组（L组，n=60）。感染性脑水肿组又按颈内动脉注射脂多糖后6h、12h、24h、48h、72h分为5个亚组（n=12）。向颈内动脉注射脂多糖LPS150μg（0．15ml）建立大鼠感染性脑水肿模型。采用HE染色、流式细胞检测和免疫纽化染色分别观察脑组织病理改变、星形胶质细胞凋亡、胶质纤维酸性蛋白（GFAP）和iNOS表达情况。结果与C组和S组比较，L组大鼠星形胶质细胞胞体变大、突起增多；细胞内GFAP和iNOS表达增强，12h达高峰，除72h组，其余亚组均有统计学差异（P〈0．05）；各亚组星形胶质细胞凋亡增多（P〈0．05），24h凋亡最显著。C组和S纽比较无统计学意义（P〉0．05）。结论感染性脑水肿后星形胶质细胞凋亡增加，异常活化，分泌iNOS，参与感染性脑水肿的形成，在脑水肿的发生发展中发挥重要作用。

Apoptosis and Activation of Astrocytes in Rats During Infectious Brain Edema Induced by Lipid Polysaccharide

Objective By observing apoptosis and activation of astroeytes and its expression of iNOS in rats with infectious brain edema induced by lipid polysaceharide （LPS） , it is planed to discuss the effects of astroeyte on LPS-indueed eneephaledema. Methods Eighty four a- dult SD male rats were randomly divided into 3 groups：control group （group C, n = 12） , saline group （group S, n = 12） , LPS group （group L, n = 60）. Group L was divided into 5 subgroups according to different time points after injecting LPS：6 h, 12 h,24 h,48 h,72 h （n = 12, each subgroup）. Cerebral edema was induced by carotid injection with LPS （ 150 μg）. HE staining,flow cytometry and immunohistochemistry methods were used respectively to measure the pathological morphology of brain tissue, the apoptosis of astrocytes and the expression of GFAP and iNOS. Results Compared with group C and group S, astroeytes of group L were swollen with increased neurite;exeept group L ：72 h, the expression of iNOS and GFAP were significantly increased （ p 〈 0. 05）, up to a peak at 12 h. The apoptosis of astroeytes were significantly increased after LPS injection （ p 〈 0.05 ）, with a peak time at 24 h. No significant difference was found between group C and group S （ p 〈 0. 05 ）. Conclusion Astroeytes participate and play an important role in the formation and development of infectious cerebral edema by inducing apoptosis and producing iNOS after its activation.