Effect Of Mild Hypothermia On The Expression Of HSP27 And HSP70 In Hippocampus Of Kainic Acid Induced Status Epilepticus In Rats

Objective: To investigate the intervention effects of mild hypothermia pretreatment and mild hypothermia treatment on status epilepticus(SE) rats and its relationship with the expression of Heat-shock protein 27(HSP27) and Heat-shock protein 70(HSP70) in rats, in order to probe the anti-epileptic mechanism of mild hypothermia.Methods: An animal model of status epilepticus(SE) was established in rats by intracerebroventricular injection of Kainic acid(KA). 135 male SD rats were randomly divided into normal control group(group N), sham operation group(group F), SE model group(group SE), mild hypothermia pretreatment group(group MP),and mild hypothermia treatment group(group MT).Each group was further divided into three subgroups(6h, 12 h and 24 h after SE, n =9), 9 rats of each subgroup. Morphologic changes of the hippocampal neurons were observed by HE staining, while the expressions of HSP27 and HSP70 in the CA3 of hippocampal tissue were measured by immunohistochemical techniques. Results: Seizure levels and neuronal damage of rats in group MP and group MT were lower than those in group SE. In hippocampal tissue, HSP27 and HSP70 expression of three subgroups in group SE increased significantly than those in group F(P<0.05); HSP27 and HSP70 expressions of three subgroups of group MP and group MT increased significantly than those in group SE(P<0.05). No statistically differences of HSP27 and HSP70 expression were found between group N and group F(P > 0.05). Up-regulation of HSP27 and HSP70 expression displayed an upward tendency from 6h to 24 h time point after SE in the same group. Conclusion: Mild hypothermia have some antiepileptic effects. The anti-epileptic effects of mild hypothermia are concerned with lessen of neuronic damage, the mitigation of seizure degree, and the up-regulation of HSP27 and HSP70 expression.