外侧液压打击诱导大鼠外伤后癫痫模型的制作

Establishment of posttraumatic epilepsy model induced by lateral fluid-percussion injury in rats

目的通过外侧液压打击诱导大鼠重度脑外伤,研究外伤后早期和晚期癫痫发作的行为学及皮层脑电表现,探讨利用此模型模拟人类外伤后癫痫的可行性。方法 24只雄性SD大鼠随机分成A、B、C三组,A组为开颅+打击+安电极组(16只)、B组为开颅+安电极组(4只)、C组为安电极组(4只)。所有大鼠分别于致伤后1周内和4周后监测癫痫的行为发作和脑电发作,每4周监测1周,共监测12周,记录早期发作和晚期发作的表现、频率及持续时间。对实验中死亡的大鼠进行组织病理学检查,分析死亡原因。结果 A组死亡7只(43.7%),其中打击后立即死亡6只,死于感染1只;B组死于感染1只(25%);C组无死亡。非感染死亡大鼠的组织病理显示为硬膜下出血、蛛网膜下腔出血和局部脑挫裂伤。A组存活的9只大鼠中早期发作有1只(11.11%),发作频率为3次/周,发作时程为24±8s;晚期发作有4只(44.44%),发作频率为2.2±1.6次/周,发作时程46±13s;对照组(B组和C组)未见发作。结论外侧液压打击诱导大鼠外伤后癫痫的行为和脑电表现与人类相似,晚期发作是模拟人类外伤后癫痫的理想模型。

Objective In order to monitor and analyze the behavioral and electrocorticographical features of early and late seizures in rats,severe traumatic brain injury was induced in rats by lateral fluid percussion injury（LFPI）,The feasibility of imitating human posttraumatic epilepsy（PTE）with the animal model was discussed.Methods Twenty-four adult male Sprague-Dawley rats were randomized into group A,B and C.In group A,sixteen rats received craniotomy,LFPI and electrode implantation.In group B,four rats received craniotomy and electrode implantation.Four rats in group C received only electrode implantation.Behavioral and electrocorticographical seizures were monitored with video-EEG for one week in all rats immediately after injury,then every four weeks till the end of the study（twelve weeks）.Behavioral features,frequency and duration of early and late seizures were recorded.Histology was observed in dead rats.Results Six rats（43.7%）died of LFPI and one infection in group A,one rat（25%）died of infection in group B and no rat died in group C.Histology indicated subdural,subarachnoid hemorrhage and focal cortical contusion.Early posttraumatic seizures were observed in one rat（11.11%）of group A,at a frequency of three times per week and mean seizure duration 24±8 seconds;Late seizures were observed in four rats（44.44%）in group A,with the frequency of 2.2±1.6 seizures per week and duration of 46±13 seconds.Eight rats in group B and C had no seizure during the study.Conclusion Our results suggested that the PTE model induced by LFPI in rats was similar to human PTE in behavioral and electrocorticographic features.Late seizures could be regarded as an ideal PTE model.