绞股蓝总皂苷对全脑缺血再灌注大鼠海马区c-jun蛋白表达的抑制作用

 目的 探讨绞股蓝总皂苷(GP)对全脑缺血再灌注大鼠海马区c-jun蛋白表达的影响.方法 用改良的Pulsinelli 4-血管阻断(4-VO)法制做大鼠急性全脑缺血再灌注损伤模型,分别按照再灌注6 h、24 h、72 h取材,应用免疫组织化学法标记各实验组大鼠脑组织海马区c-jun蛋白表达数量.结果 与对照组比较,模型组Jun蛋白表达最高.各组海马区的Jun蛋白表达随着缺血再灌注时间的延长呈递减趋势(再灌注6 h＞再灌注24 h＞再灌注72 h).再灌注6 h各实验组的Jun蛋白表达结果是:模型组＞GP低剂量给药组＞GP高剂量给药组.与模型组相比,绞股蓝总皂苷2个剂量组在不同灌注时间(6 h、24 h、72 h)均具有显著的抑制JUN蛋白表达的作用.结论 绞股蓝总皂苷可明显下调JUN蛋白的表达,具有抑制全脑脑缺血再灌注时神经细胞凋亡作用,从而改善受损的神经功能.GP对急性全脑缺血模型大鼠的脑损伤的预防保护有一定的剂量相关趋势.

Effects of gypenosides on expression of Jun protein in hippocampus of rats with cerebral ischemia-reperfusion injury

Objective To study the inhibitive effect of gypenosides on expression of immediate early gene c-jun in hippocampus of rats with cerebral ischemia-reperfusion injury.Methods Modified Pulsinelli 4vessel occlusion(4-VO) was used to develop the rat model of acute cerebral ischemia-reperfusion.Brain specimens were taken 6 h,24 h,and 72 h after cerebral ischemia-reperfusion injury.ABC immunohistochemical anslysis was carried out to observe the expressions of Jun protein at different times in hypocampus of rats receiving high and low pocampus dosage GP.Results The expression of Jun protein was highes in the model group,compared with the blank group.The expression of Jun protein in hippocampus of experimental groups decreased progressively with increasing time of reperfusion(6 h>24 h>72 h).The expression of Jun protein in the groups of reperfusion 6 h ranked in the following order: model group >high GP dosage group >low GP dosage group.Compared with model group,high and low dosage GP groups showed noticeable inhibitive effect on expression of Jun protein in hippocampus at different cerebral ischemia-reperfusion times.Conclusions GP down-regulates the expression of c-jun and inhibits the apoptosis of nerve cells,thus preventing cerebral injury in ischemia-reperfusion rats,and improving the function of impaired nerves;the protective role is related with the dosage of GP.