Effect of Tetramethylpyrazine and ischemic preconditioning on expression of HSP70 and learning-memory capacity of gerbils after cerebral ischemia
AIM:To study the effect and the possible protective mechanism of TMP (Tetramethylpyrazine) combined with ischemic preconditioning on learning-memory function after orebrain ischemia- reperfusion injury in gerbils. METHODS: Gerbils (n = 80) were divided randomly into 4 groups: control group, ischemia group, ischemia preconditioning group (IP), ischemia preconditioning + TMP treatment group. Transient forebrain ischemia model was formed by bilateral common carotid artery occlusion according to the description of Kirino's method. On 3 - 7 d after operation, learning-memory function were performedwith 4-PTT dry path maze. Changs of neuron morphous in hippocampal CA1 region were observed by HE staining. The expression levels of HSP70 were detected by immunohistochemistry and western Blot. Neurons apoptosis were detected by TUNEL method. RESULTS: Compared with control group, there were higher learning -memory function defect, lower density of survival neurons, more apoptotic neurons and higher expression levels of HSP70 in ischemia group (P ＜ 0.05); Compared with ischemia group, there were lower learning-memory function defect, higher density of survival neurons, fewer apoptotic neurons and more higher expression levels of HSP70 in IP group and IP + TMP treatment group. What's more, the above mentioned indexes changed more significantly in IP + TMP treatment group (P ＜ 0.05). CONCLUSION: TMP can enhance the effect of ischemic tolerance induced by ischemic preconditioning. TMP combined with IP can further improve the learning-memory function after forebrain ischemia-reperfusion damage in gerbils. One of molecular mechanisms is related to their cooperative regulation effects on HSP70 expression and reducing neurons apoptosis.
tetramethylpyrazinelearning-memoryischemia preconditioningcerebral ischemiaheat-shock protein 70ischemic tolerance
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万方数据
维普
