侧脑室注射神经肽Y对癫痫大鼠脑源性神经营养因子表达的影响

Effects of Lateral Ventricle Infusion with Neuropeptide-Yon Expression of Brain-derived Neurotrophic Factor in Hippocampus after IL-1β-induced Epileptic Seizure in Rats

目的研究脑室内注入神经肽Y(NPY)对白细胞介素-1β(IL-1β)致痫大鼠海马结构内脑源性神经营养因子(BDNF)表达的影响。方法将16只健康雄性W istar大鼠随机分为实验组(n=8)和对照组(n=8)。实验组脑室注射NPY(6nmol/5μl),对照组给予等容量生理盐水,5m in后再注射IL-1β(2500U/kg),观察痫性发作持续时间并于痫性发作后2小时处死动物。用免疫组化方法观察齿状回(DG)和海马CA3区BDNF的免疫组织化学反应。结果实验组痫性发作时间短于对照组。实验组DG颗粒细胞层、分子层的BDNF免疫反应性高于对照组相应各层,各组比较有显著性差异(P<0.01)。实验组CA3区锥体细胞层、放射层及腔隙层免疫反应性均高于对照组相应各层,各组比较有显著性差异(P<0.01)。实验组DG分子层和CA3区放射层及腔隙层免疫反应性分别高于颗粒细胞层和锥体细胞层免疫反应性,各组比较有显著性差异(P<0.01)。CA3区分子层未见BDNF免疫反应性表达。结论脑室内注射NPY可缩短痫性发作时间,促进致痫大鼠海马内BDNF的表达。

Objective To study the effects of lateral ventricle infusion with neuropeptide Y （NPY） on brain-derived neurotrophic factor （BDNF） expression in hippocampus after IL-1β induced seizure in Wister rats. Methods 16 male healthy adult Wistar rats were divided into NPY experimental group and control group randomly. In NPY group（8 rats）, NPY （6 nmoL/5μl） was injected into lateral ventricle before IL-1β induced seizure. In control group（8 rats）, equal amount of normal saline solution was injected into lateral ventricle. All rats were decapitated at 2h after seizure induced by IL-1β injection into lateral ventricle （2500U/kg）. BDNF immunoreactivity was investigated in both groups by immunohistochemistry. Results The seizure duration in NPY experimental group was shorter than in control group （ P 〈 0. 01 ）. BDNF immunoreactivity in stratum granulosum and stratum moleculare of DG in NPY experimental group was higher than in control group and statistical difference was significant. In stratum pyramidale, stratum radiatum and stratum laeunosum of CA3, BDNF immunoreactivity in NPY experimental group was higher than in control group and statistical difference was significant. BDNF imunoreactivity in stratum moleculare of DG, stratum radiatum and stratum lacunosum of CA3 was higher than in stratum granulosum of DG and stratum pyramidale of CA3, respectively, and statistical difference was significant. In stratum moleculare of CA3, BDNF immunoreactivity was negative in both groups. Conclusion Lateral ventricle infusion with N PY can decrease the seizure duration and increase BDNF expression in hippocampus after IL-1β induced seizure in rats.