亚低温对新生鼠缺氧缺血性脑损伤神经细胞凋亡和胱天蛋白酶-3活性的影响

目的探讨亚低温对新生鼠缺氧缺血性脑损伤神经细胞凋亡和胱天蛋白酶-3(Caspase-3)活性的影响。方法7日龄SD大鼠分为假手术组、缺氧缺血性脑损伤常温组(HIBD组)和缺氧缺血性脑损伤亚低温处理组(亚低温组)。HIBD组行左颈总动脉结扎后.吸入氧氮混合气持续2h;亚低温组将HIBD新生鼠维持于31-32℃亚低温8h。用TUNEL法和荧光四肽底物(ACDEVDAMC)法分别检测假手术组、HIBD组和亚低温组的凋亡细胞百分率和Caspase-3活性水平。结果与HIBD组比较,亚低温组和假手术组的凋亡细胞百分率和Caspase-3活性水平显著降低。结论亚低温可减弱新生鼠HIBDCaspase-3活性.抑制神经细胞的凋亡。

Influence of Mild Hypothermia on Nervous Cell Apoptosis and Activity of Caspase-3 after Hypoxia-Ischemia Brain Damage in Neonatal Rats

Objective To study the effects of mild hypothermia on nervous cell apoptosis and activity of Caspase - 3 after hypoxia -ischemia brain damage (HIBD) in neonatal rats. Methods Seven - day SD rats were divided into sham operation group,normothermia HIBD group (HIBD group) and mild hypothermia HIBD group(mild hypothermia group). In HIBD group,the left carotid of rats was ligated and animals were exposed to 8% oxygen for 2 h.and in mild hypothermia group,hypothermia of 31 - 32 1C lasting 8 hours was used just after HIBD. L sing methods of TUNEL and AC - DEVI) - AMC, the apoptotic cell rate and Caspase - 3 activity level were determined in sham operated group, HIBD group and mild hypothermia group separatively. Results The apoptotic cell rate and Caspase - 3 activity level were significantly lower in sham - operated group and mild hypothermia group than those in HIBD group. Conclusion One of the mechanisms of brain protection by mild hypothermia may be contributed to the decrease of neural cell apoptosis and the activity level of Caspase 3 HIBD.