Effect of local mild hypothermia on expression of glial fibrillary acidic protein change after focal cerebral ischemia and reperfusion in rats

Objective To observe the effect of local mild hypothermia on expression of glial fibrillary acidic protein (GFAP) and pathological change after focal cerebral ischemia and reperfusion injury.Methods Reversible middle cerebral artery occlusion was performed with modified Koizumi's model.Male Wistar rats were randomly divided into ischemic group, hypothermia group and sham operated group.Hypothermia group and normothermia group were subdivided into 3h and 12h groups.The brain temperature was lowered to 32～33℃ in focal cerebral ischemia rodent models by feedback regulated semiconductor cooling therapy,started at 30min after the ischemic onset and maintained throughout the period of ischemia and reperfusion.The GFAP expression was investigated with immunohistochemistry and the pathological changes were evaluated by hematoxylin and eosin stained section.Results The expression of GFAP in ischemic group significantly increased.The astrocytes were swelling compared with sham operated group.The astrocyte expression of GFAP after treated with mild hypothermia decreased.Conclusion Mild hypothermia could markedly inhibit the activation and swelling of astrocyte as well as prevent pathological change.