ABSTRACT
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.