核因子κB和半胱氨酸天冬氨酸蛋白酶3在实验性蛛网膜下腔出血小鼠模型中不同时期的表达变化

The different period change of NF-κB and Caspase-3 expression in experimental SAH of mouse models

目的探讨小鼠实验性蛛网膜下腔出血(SAH)后脑组织核因子κB(NF-κB)、半胱氨酸天冬氨酸蛋白酶3(Caspase-3)在各时间点表达的变化规律,并进一步研究其与细胞凋亡的关系,为临床治疗提供理论依据。方法将小鼠随机分为正常对照组、生理盐水组和实验模型组,生理盐水组和实验模型组分别观测6个时相点:3 h、6 h、12 h、24 h、3 d、7 d,并在规定的时间点断头取脑,连续冠状切片作HE染色检测病理结果,免疫组化法观察NF-κB、Caspase-3阳性表达及TUNEL分析细胞凋亡数。结果 NF-κB在实验模型组SAH后3 h(P<0.05)开始增多,12 h(P<0.01)其表达继续上升,24 h达高峰,持续到3 d(P<0.01)仍高于生理盐水对照组,7 d后下降;Caspase-3在SAH后12 h(P<0.01)开始增多,在24 h和3 d时为差异有统计学意义(P均<0.05),7 d阳性表达恢复到正常水平,无统计学意义;并且二者与TUNEL阳性细胞的表达变化趋势基本一致。结论 SAH后NF-κB、Caspase-3阳性表达在时间上的变化趋势与神经细胞凋亡的发生密切相关,并且SAH后3 d这一时期内可成为治疗SAH的最佳时间窗。

Objective To evaluate the dynamic change of the expression of NF-KB and Caspase-3 in rat brain after experimental subaraehnoid hemorrhage （ SAH ）, and investigate the relationship between NF-KB, Caspase-3 and apoptosis after experimental SAH, to offer theoretic evidences for clinical therapy. Methods The rats were randomly assigned to normal control group, saline group and SAH group, While the saline group and SAH group was each divided into 6 subgroups according to time phase which was 3 h,6 h, 12 h,24 h,3 d and 7 d. Then The brains of rats were removed at a predetermined time and successive coronary slices with HE staining detecting pathological results, with immunohistochemistry measuring the expression of NF-KB and Caspase-3, with TUNEL staining analyzing the condition of neurocyte apoptosis. Results The expression of NF-KB in SAH began to increase at 3 h （ P 〈 0.05 ） after SAH, continued to increase at 12 h（ P 〈 0. 01 ）, reached peak on 24 h, which was still higher than saline group on 3 d（ P 〈 0. 01 ）and then 7 d began to decrease ;while the positive expression of Caspase-3 in SAH started to increase at 12 h（P 〈 0. 05 ）and revealed a very statistical significance between 24 h and 3 d（ P 〈 0. 05 ）, however, it returned to normal level without statistical significance on 7 d, which changed as the apoptosis did. Conclusion The positive cell expression changes over time trending of the NF-KB and Caspase-3 after SAH are closely related to the occurrence of nerve cell apoptosis, and the same period after 3 days of SAH may be the best time window of the treatment.