Nedl1基因敲除鼠匹鲁卡品癫痫模型的建立

Establishment of an epileptic model of pilocarpine in Nedl1 knockout mice

目的通过Nedl1(NEDD4-like ubiquitin protein ligase-1)基因敲除鼠(Nedl1-/-)构建匹鲁卡品癫痫模型,探讨Nedl1基因与癫痫之间的关系。方法C57BL/6小鼠通过Cre-Loxp系统构建Nedl1-/-小鼠。选择相同年龄野生型小鼠(Nedl1+/+)及Nedl1-/-小鼠,腹腔注射匹鲁卡品诱导癫痫发作,对两组小鼠癫痫发作情况进行统计,并且对比未造模时及癫痫模型建模1个月后两组小鼠海马Nissl染色、NPY(neuropeptide Y)染色。结果与Nedl1+/+小鼠相比,Nedl1-/-小鼠癫痫发作等级较轻(P=0.000),癫痫发作次数较少(P=0.004),首次出现3级以上发作的时间较长(P=0.016)。癫痫模型建模后Nedl1-/-小鼠全部存活,而Nedl1+/+小鼠死亡率为46.4%。癫痫模型建模后1个月Nissl染色显示Nedl1+/+小鼠海马CA1区细胞计数明显减少,DG区的细胞排列紊乱,明显固缩,Nedl1-/-小鼠海马Nissl染色无明显变化。癫痫模型建模后1个月NPY免疫荧光染色显示Nedl1+/+小鼠苔藓纤维发芽较Nedl1-/-小鼠明显。结论Nedl1-/-小鼠癫痫发作严重程度以及死亡率明显低于Nedl1+/+小鼠,癫痫模型后1个月,Nedl1-/-小鼠海马神经元损害及苔藓纤维发芽情况较Nedl1+/+小鼠弱。

Objective To explore the relationship between Nedl1 gene and epilepsy by constructing a pilocarpine epilepsy model in Nedl1(nedd4-like ubiquitin protein ligase-1)knockout mice(Nedl1-/-).Methods C57BL/6 mice were selected to construct Nedl1-/-mice by the Cre-Loxp system.Wild-type mice(Nedl1+/+)and Nedl1-/-mice of the same age were selected to induce epileptic seizures by intraperitoneal injection of pilocarpine.The seizures of the two groups were counted,and the hippocampal Nissl staining and neuropeptide Y(NPY)staining of two groups were compared before and after establishing the epilepsy model.Results Compared to Nedl1+/+mice,the seizures in Nedl1-/-mice were milder(P=0.000),less frequent(P=0.004),and the severe seizures(Racine scale score>3)occurred later(P=0.016).All Nedl1-/-mice survived,while the mortality rate of Nedl1+/+mice was 46.4%.One month after the establishement of epilepsy model,the Nissl staining showed that the number of cells in the hippocampal CA1 region of Nedl1+/+mice significantly decreased,and those in the DG region were disordered and consolidated.Nedl1-/-mice hippocampal Nissl staining showed no significant changes.The immunofluorescence staining of NPY showed that the mossy fiber sprouting in Nedl1+/+mice was more obvious than in Nedl1-/-mice.Conclusion The severity and mortality of seizures in Nedl1-/-mice are significantly lower than those in Nedl1+/+mice.One month after the establishement of epilepsy model,neuronal damage and mossy fiber sprouting in the hippocampus of Nedl1-/-mice are milder than those in Nedl1+/+mice.