青春期大鼠癫痫发作后海马齿状回颗粒细胞层神经细胞增殖的改变

目的:探讨青春期大鼠癫痫发作后海马齿状回颗粒细胞层神经细胞数量的变化。方法:选择健康4周龄雄性SD大鼠,应用氯化锂-匹罗卡品药物点燃造模,造模成功后根据取脑组织时间分为24 h组、2周组、4周组,并设相应的对照组。溴脱氧尿嘧啶核苷(BrdU)标记后免疫荧光染色,用激光共聚焦观察大鼠海马齿状回(DG)颗粒细胞层BrdU阳性细胞。结果:24 h和2周实验组BrdU阳性细胞显著增多,分别较对照组增加55.1%和39.6%,2周实验组比24 h实验组降低15.5%(P<0.05);4周实验组BrdU阳性细胞数较对照组无明显差异(P>0.05)。结论:青春期大鼠癫痫发作可引起海马齿状回颗粒层神经细胞增殖的升高,但随着时间的延长有下降的趋势,至4周左右神经细胞的增殖趋于正常。

The proliferation of neurons in the granular layer of hippocampal dentate gyrus in epileptic adolescent rats

Objective: To investigate the proliferation of neurons in the granular layer of hippocampal dentate gyrus(DG) in epileptic adolescent rats.Methods: Lithium-pilocarpine(LI-PILO) was administered to four-week-old male Sprague-Dawley rats to induce status epilepticus(SE).After successfly induced SE,the rats were randomly divided into six groups according to the time points of bromodeoxyuridine(BrdU) injection: 24 h group,2 weeks group,4 weeks group,and the corresponding control groups.By using immunohistochemistry method,the expressions of the BrdU in the granular layer of DG were observed under a laser confocal microscope.Results: The BrdU positive cells in 24 h group and 2 weeks group were significantly more than those in control groups(P<0.05),increased 55.1% and 39.6%,respectively;and the expression of BrdU in 2 weeks group was lower than that of 24 h group(P<0.05);while there was no obvious difference between 4 weeks group and the corresponding control group(P>0.05).Conclusion: SE can increase the proliferation of neurons in the granular layer of hippocampal DG in the adolescent rats,but this increase displays a downward trend over time,and tends to be normal after 4 weeks.