The effect of mild hypothermia on mice cerebral ischemia-reperfusion nerve cell apoptosis

Abstract

Objective To observe the treatment effect of mild hypothermia on cerebral ischemiareperfusion nerve cell apoptosis, and study its mechanism from the molecular level. Methods SD rats were employed to produce cerebral ischemia-reperfusion injury model, then were divided into mild-hypothermia treatment group and control group. The cell apoptosis was detected by TUNEL mothod, during the mild hypothermia 24 h, 48 h, 72 h, and 24 h, 48 h, 72 h, 96 h and 120 h after rewarming, and RT-PCR method was used to detect the mRNA expression apoptosis gene Caspase-3, Fas and Bcl-2 at all the above time points. Results The apoptosis cell number during mild hypothermia therapy in mild hypothermia group was less than the control group (P＜0. 05), then increased gradually after rewarming, till to 72 h there was no significant difference between two groups (P ＞ 0. 05). And the mRNA expression level of Caspase-3, Fas and Bcl-2 during mild hypothermia therapy in mild hypothermia group were lower than the control group (P ＜ 0. 05), and increased with rewarming, till to 72 h after rewarming there was no significant difference between two groups (P＞0.05). Conclusion Mild hypothermia can reduce the number of nerve cell apoptosis in the process of cerebral ischemia and reperfusion, but the apoptosis rate rise rapidly with rewarming, it suggests that nerve cells will be rescued as soon as possible during mild hypothermia. Key words: Hypothermia therapy; Apoptosis; Gene expression; Rats