Effects of focal cerebral ischemic preconditioning on expression of tumor necrosis factor-alpha in rats

Objective To explore the effects of focal cerebral ischemic preconditioning on the expression of tumor necrosis factor-alpha and the relationship of tumor necrosis factor-alpha and ischemic tolerance. Methods The animal model of focal cerebral ischemic tolerance was used. 30 SD rats were divided into 3 groups : IPC+MCAO group,SS+MCAO group and SS+SS group. The infarct volume and histological changes with HE staining were evaluated .The expression of tumor necrosis factor-alpha was evaluated by immunohistochemistry. Results Focal cerebral ischemic preconditioning significantly reduced the following infarct volume and the damage of histology.The interagrated optical density in IPC+MCAO group and SS+MCAO group were (8109.53±571.21) and (10704.72±584.01) respectively,which had statistic significance (F=233.59,P0.05). Conclusions Focal cerebral ischemic preconditioning can protect brain and induce ischemic tolerance. Down-regulation of the expression of tumor necrosis factor-alpha may play an important role in the induction of endogenous neuroprotection.