Tau蛋白在点燃大鼠海马苔藓纤维出芽中的作用探讨

The Role of Tau Protein in Hippocampus Mossy Fiber Sprouting of Kindling Rat

目的观察总tau蛋白及其p-ptauser202在戊四氮点燃癫模型海马中的表达变化,探讨其在苔藓纤维出芽中的作用。方法 180只雄性SD大鼠随机分为对照组(腹腔注射生理盐水)和模型组(腹腔注射戊四氮),均n=90。于不同的时间点应用Timm染色观察苔藓纤维出芽,免疫组化和Western blot检测各时间点海马总tau蛋白及p-ptauser202蛋白表达情况。结果模型组各时间点CA1、CA3、DG区苔藓纤维出芽较对照组明显增多,差异有统计学意义(P<0.05);模型组第1周CA1区、CA3区,第2周DG区的p-ptauser202蛋白表达与对照组比较明显增多,差异均有统计学意义(分别为CA1区P<0.05,CA3区P<0.01,DG区P<0.01);门区(H区)tau蛋白及p-ptauser202蛋白在各时间点的表达明显增多,差异有显著统计学意义(P<0.01);对照组无动态变化。结论 tau蛋白可能通过其磷酸化水平的增高参与癫点燃大鼠的苔藓纤维出芽,在癫的发生和发展中起重要作用。

Aim To investigate total tau protein, its phosphorylated-ptauser 202 expression in pentylenetetrazol-kindling epileptic rat hippocampus, and its phosphorylation in the developing of epilepsy. Methods 180 male SD rats were divided randomly into normal control group（90 rats） and epilepsy group（90 rats）. SD rats in normal control were injected intraperitoneally with physiological saline. The models of epilepsy were established by intraperitoneal injection ofpentylenetetrazol daily. Total tau protein and its phosphorylation at Set 202 were detected in hippocampal region by using immunohistochemistry and Westem-blot, meanwhile the state of mossy fiber sprouting was observed by using Timm staining. Results In all the periods the mossy fiber sprouting in CA1, CA3 and DG regions increased obviously in the epilepsy group, and had significant difference compared with the normal group（P〈0.05）. A significant increase of p-ptauser 202 expression came at 1 week in CA1 and CA3 regions CAI（P〈0.05）, CA3（P〈0.01）, however at 2 week in DG（P〈0.05）. In hilus region total tau protein and p-ptauser 202 increased significantly contrast to the control （P〈0.01）. Conclusion Tau protein may take part in the hippocampus mossy fiber sprouting through increasing the level of tan phosphorylation in kindling rat, and play an important role in the development of epilepsy.