反复高热惊厥大鼠脑内脑源性神经营养因子表达及神经元凋亡分析

Expression of brain-derived neurotrophic factor and apoptosis in the brain of rats with repeated febrile seizures

摘要:

目的：研究大鼠反复高热惊厥（FS）后脑源性神经营养因子（BDNF）的改变及神经细胞凋亡情况。方法：51只雄性SD大鼠按随机数字法随机分为正常对照组（NC组），高热对照组（HC组）和高热惊厥组（FS组），热水浴法建立FS模型。酶联免疫吸附试验（ELISA）测定海马匀浆中BDNF水平，免疫组化法检测BDNF在脑组织各区的表达，原位末端标记法（TUNEL）检测脑组织细胞凋亡，统计学处理采用SPSS13.0统计学软件处理。结果：ELISA 法测得的FS组海马BDNF水平（89.9±12.5 ng/g）明显高于NC组（54.4±18.9 ng/g）和HC组（64.1±15.0 ng/g）（P＜0.01），FS组各脑区BDNF阳性神经元OD值亦明显高于NC组和HC组（P＜0.01）；FS组脑组织各区凋亡指数（AI）均明显高于NC组与HC组（P＜0.01），且脑组织各区细胞凋亡程度与BDNF在脑组织各区的表达呈正相关（r=0.332，P＜0.05）。结论：反复FS后大鼠脑内BDNF表达明显增加，并且与神经细胞的凋亡相关。［中国当代儿科杂志，2010，12（5）：382-385］

Abstract:

OBJECTIVE: To study the changes of brain-derived neurotrophic factor (BDNF) following repeated febrile seizures in rats and its possible correlation with neurocyte apoptosis. METHODS: Fifty-one male Sprague-Dawley (SD) rats were randomly assigned to three groups: normal control (n=14), febrile seizure (FS, n=18), hyperthermia alone (n=19). Febrile seizures were induced by hot water bath. The level of BDNF in the hippocampal homogenate was measured using ELISA and the expression of BDNF in various brain regions was measured by immunohistochemistry. The neurocyte apoptosis of the brain was determined by TdT-mediated biotinylated-dUTP nick end labling (TUNEL). RESULTS: The level of BDNF in the hippocampus in the FS group（89.9±12.5 ng/g）was higher than that in the normal control group（54.4±18.9 ng/g）and in the hyperthermia alone group （64.1±15.0 ng/g） (P<0.01). The OD value of BDNF positive neurons in various brain regions of the FS group was significantly higher than that of the normal control group (P<0.01) and the hyperthermia alone group (P<0.01). The FS group had significantly higher apoptotic index in various brain regions than the normal control and the hyperthermia alone groups (P<0.01). There was a positive correlation between the expression of BDNF and the apoptotic index in various brain regions (r=0.332, P＜0.05）. CONCLUSIONS: BDNF expression in the brain increases following repeated febrile seizures in rats, and the increased BDNF expression is correlated with neurocyte apoptosis.［Chin J Contemp Pediatr, 2010, 12 (5):382-385］