颞叶癫痫模型大鼠行为及海马突触蛋白的表达变化

The behavior and hippocampal synaptic protein expression changes of temporal lobe epilepsy model rats

目的:研究颞叶癫痫(TLE)模型大鼠行为及海马突触蛋白的表达变化。方法:将SD大鼠分为对照组(control)和颞叶癫痫组(TLE),用腹腔注射氯化锂和匹罗卡品的方法制备TLE模型,高架十字迷宫和三箱交互实验检测大鼠情绪和社交行为,免疫组织化学染色和Western Blot检测神经突触素I(Syn1)、突触后致密蛋白95(PSD95)和桥蛋白(gephyrin)的表达特征。结果:与Control组比,TLE组大鼠焦虑样行为增加(P<0.01),社交新颖性下降(P<0.01)。各组大鼠海马区均可见Syn1、PSD95和gephyrin免疫阳性染色,以CA3区的始层和透明层为主。在TLE 1 d~3 d,CA3区三种分子阳性染色较control组略减少(P<0.05,P<0.01),透明层染色渐呈颗粒状。在7 d和14 d三种蛋白免疫阳性染色逐渐升高,28 d再次下降,但均低于control组(P<0.05,P<0.01);透明层PSD95染色呈条带状,Syn1和gephyrin染色呈小片状。Western Blot结果显示:在TLE 1 d~3 d,Syn1、PSD95和gephyrin表达下降(P<0.05,P<0.01);在7 d和14 d表达略升高,28 d表达再次下降,但低于control组(P<0.05)。结论:TLE大鼠社交新颖性下降和焦虑样行为的增加,与海马Syn1、PSD95和gephyrin的表达降低有关。

Objective:To study the behaviors and the hippocampal synaptic proteins expression changes of temporal lobe epilepsy(TLE)model rats.Methods:SD rats were divided into control group and TLE group,the TLE model were induced by lithium chloride and pilocarpine,the behavior changes were detected by elevated plus maze and three⁃box interaction test,and the expressions of synapsin1(Syn1),postsynaptic density 95(PSD95)and gephyrin in the hip⁃pocampus were observed by immunohistochemistry(IHC)and Western Blot.Results:The behavioral results showed that the anxiety⁃like behavior in TLE group was significantly higher than the control group(P<0.01);The social nov⁃elty of TLE group was lower than control group(P<0.01).The IHC results showed that the positive staining of Syn1,PSD95 and gephyrin were observed in the hippocampus in every group,mainly in the lamina propria and stratum lucid⁃um of the CA3 region.Compared with control group,the positive staining of three molecules in CA3 decreased slightly from day 1 to day 3 in TLE groups(P<0.05,P<0.01),and the positive staining in lucidum gradually became granu⁃lar.The immunostaining positive of Syn1,PSD95 and gephyrin increased gradually in TLE 7 d and 14 d,and decreased again in 28 d,but all lower than those in control group(P<0.05,P<0.01).The Syn1,PSD95,and gephyrin posi⁃tive staining in the stratum lucidum showed bands and sheets,respectively.Western Blot results showed that the the ex⁃pressions of Syn1,PSD95 and gephyrin in the hippocampus in TLE 1 d and 3 d were lower than those in control group(P<0.05,P<0.01),and slightly increased in TLE 7 d and 14 d,decreased again in TLE 28 d,but still lower than those in control group(P<0.05).Conclusions:The decreases of social novelty,the increase of anxiety⁃like behavior of TLE rats are related to the decreased expressions of Syn1,PSD95 and gephyrin in the hippocampus.