戊四氮致癎大鼠不同脑区神经元特异性烯醇酶的表达及意义

Expression of Neuron - Specific Enolase in Brain of Rats with Epilepy Induced by Pentylenetetrazol

目的研究神经元特异性烯醇酶(NSE)的改变.探讨戊四氮(PTZ)致癎大鼠癫癎(EP)后脑组织的损坏情况。方法SD大鼠50只,随机分为对照组(A组,n=10)及实验组(n=40)。A组注射生理盐水,实验组腹腔注射PTZ50mg/(kg·次)。根据EP发作分级,0-1级7只,为B组,立即取脑;2级以上33只,于EP发作后0h(C组,n=10)、6h(D组,n=11)、24h(E组,n=10)、72h(F组.n=2)取脑。取躯干血后分别取海马、中脑、纹状体和额叶皮质。采用酶标法测血清和各脑区NSE值;以S-P免疫组织化学染色法染色,观察各组大鼠海马NSE表达。结果EP后各脑区和血清NSE均明显高于对照组;既使无EP大发作.但有兴奋症状的大鼠上述区域和血清NSE亦高于对照组。动态观察EP后不同时间段,发现中脑NSE在EP后6h达到高值.余脑区EP后即达高值,后出现下降,提示额叶、海马和纹状体神经损伤在前,而中脑神经损伤在后。免疫组织化学染色显示EP大发作后海马NSE表达明显增加,EP后72h与对照组相似。结论EP发生后NSE明显升高,尤其是海马区,表明EP可造成大脑神经细胞的损坏。

Objective To evaluate the effect of epileptogenesis upon brain damage, and the changes of neuron-specific enolase （NSE） in serum and brains of pentylenetetrazol（PTZ） induced rats. Methods Fifty male adult SD rats were randomly divided into experimental group and control group. The experimental group was injected intraperitoneally（IP） with PTZ （50 mg/kg） ,and the control group （Group A, n = 10） was injected with IP with normal saline. The treatment group was divided into seizured group and without seizure group（Group B, n = 7） which was decapitated inwnediately. Groups of seizures were .sacrificed at T= 0 h （Group C, n = 10 ）, 6 h（Group D, n = 11 ） and 24 h（Group E, n=10） after developing seizures. Blood samples were collected before .scarify. Enzyme - immunoassay（EIA）was used to evaluate the changes of NSE in mesencephalon, hippocampus, striattum, frontal cortex and serum. Expression of NSE in hippocampus was detected by immunocytochemical technics. Results The levels of NSE in serum, striatum and frontal cortex of Group B were significantly higher than those of Group A（ P〈0.05 ）, it showed significant difference in hippocampus between 2 groups（P〈0.001 ）, and no difference was found in mesencephalon of Group C, D. The level of NSE in the .seizure group was significantly higher than that of control group, but no difference was found between .seizure and non - .seizure group. The levels of NSE in frontal cortex,striatum and hippocampus of seizure group were decreased after seizure, and the levels of NSE in serum and mesencephalon got its highest at 6 hours after .seizure, and then decrea.sed. At 24 hours after seizure, the level of NSE in hippocampus and serum were still significantly higher than those of control group（ P〈0.01 ）. Conclusion The significant increases of NSE in serum and brains of PTZ- induced rats shows the damage of brain tissue after seizure.