雷帕霉素对中年期MCD大鼠学习记忆能力及自发性癫痫的影响

发布时间：2018-05-03 08:18

本文选题：雷帕霉素 + 大脑皮质发育畸形　；参考：《西南医科大学》2017年硕士论文

【摘要】：目的:观察雷帕霉素对中年期MCD大鼠模型学习记忆能力及自发性癫痫的影响,探讨雷帕霉素对MCD是否具有保护作用,从而对难治性癫痫的药物治疗提供新的依据。方法:将怀孕17天大鼠进行X射线照射,所生子一代大鼠随机选取为MCD大鼠模型组,将未照射怀孕大鼠所生子一代大鼠随机选取设定为正常对照组,两组大鼠分别培养至51周(中年期)。各组内分为雷帕霉素组、溶剂组和生理盐水组,分别予以腹腔注射上述药物30天。每组大鼠药物注射前后进行Morris水迷宫检测,测定逃生潜伏期、目标象限路程比、穿越平台次数,判断其学习记忆能力前后有无变化。后行脑电图监测,统计各组大鼠左右两侧大脑半球痫性波发放次数。最后灌注固定大鼠,取出脑组织,测定大鼠脑组织前后径、左右径、上下径、体积、重量,行石蜡切片、HE染色。视频监控持续药物注射前、中、后共三个月,各阶段选取8天人工观察自发性癫痫发作情况。结果:1、Morris水迷宫逃生潜伏期:注射药物前比较,模型组和正常组显示出明显差异,模型组内任意一组与正常组内任意一组比较差异均有意义。模型组药物注射前后比较,各组前后对应天数逃生潜伏期差异无统计学意义。Morris水迷宫目标象限路程比和穿越平台次数:注射药物前比较,模型组内雷帕霉素组与正常组内雷帕霉素组比较,差异有意义。模型组药物注射前后比较,各组注射前后对应天数对比差异均无意义。2、脑电图:双侧大脑半球对应部位(额叶、顶叶、海马)同时放电。正常组大鼠脑电图仍显示尖波、棘波、棘慢复合波,平均每分钟发作次数明显低于模型组,正常组内各组差异无统计学意义。模型组内痫性尖波发作次数雷帕霉素组溶剂组生理盐水组;雷帕霉素组与后两组分别比较差异均有统计学意义;溶剂组、生理盐水组比较差异无统计学意义。模型组内雷帕霉素组和正常组内溶剂组、生理盐水组比较差异无统计学意义。3、长程视频监控:正常组及模型组均未观察到Racine分级达3级及其以上者。4、大体、病理结果:与正常组相比,模型组脑组织体积、重量、前后径、左右径、上下径均减小,差异有统计学意义。正常组内各组差异无统计学意义;模型组内各组差异无统计学意义。HE染色结果显示正常组皮层结构清晰,分层明显,细胞排列整齐,未见异常神经元;模型组雷帕霉素组出现胼胝体缺失,脑室扩大,皮层结构紊乱,神经元极性紊乱、疏密不均,可见异常神经元,海马CA1区可见结节。结论:本实验条件下:1、195cGyX射线照射母鼠所生子一代制备MCD大鼠模型成功,此方法简单可靠。2、雷帕霉素可能降低中年期MCD大鼠模型痫性波的发生率。3、雷帕霉素对中年期MCD大鼠模型学习记忆能力无明显改善作用,且对已形成的脑部病理损害无逆转作用。
[Abstract]:Aim: to observe the effects of rapamycin on learning and memory ability and spontaneous epilepsy in middle-aged MCD rats, and to explore whether rapamycin has protective effect on MCD and provide a new basis for drug treatment of intractable epilepsy. Methods: after 17 days of pregnancy rats were exposed to X ray, the first generation of offspring was randomly selected as MCD rat model group, and the first generation of unirradiated pregnant rats was randomly selected as normal control group. The rats in the two groups were cultured to 51 weeks (middle age). Each group was divided into rapamycin group, solvent group and saline group. The Morris water labyrinth was detected before and after drug injection in each group. The latency of escape, the ratio of target quadrant distance to distance, the times of crossing the platform were determined to determine whether the ability of learning and memory changed before and after the drug injection. After EEG monitoring, the number of epileptic waves in the left and right cerebral hemispheres of the rats in each group was counted. At last, the rat brain tissue was fixed by perfusion, and the anteroposterior, left and right diameters, superior and inferior diameters, volume and weight of brain tissue were measured, and the paraffin sections were stained with HE. Before, during and after three months of continuous drug injection, 8 days were selected to observe the spontaneous seizures. Results the escape latency of the water maze was significantly different between the model group and the normal group before injection, and there was significant difference between any group in the model group and any group in the normal group. There was no significant difference in the escape latency of the corresponding days in the model group before and after injection. Morris water maze target quadrant distance ratio and the times of crossing the platform: comparison before injection; There was significant difference between the model group and the normal group. There was no significant difference in the corresponding days before and after injection in the model group. Electroencephalogram (EEG): the corresponding parts (frontal lobe, parietal lobe, hippocampus) of bilateral cerebral hemispheres were discharges at the same time. The EEG of normal group still showed sharp wave, spike wave, spine-slow complex wave, the average attack times per minute was significantly lower than that of model group, but there was no significant difference in each group in normal group. The number of epileptic spikes in the model group was significantly higher than that in the solvent group and the rapamycin group. There was no significant difference between the solvent group and the latter two groups. There was no significant difference between the solvent group and the saline group. There was no significant difference between the model group and the normal group. There was no significant difference between the normal saline group and the model group. The long-term video surveillance showed that no Racine grade of grade 3 or above was observed in the normal group and the model group. Pathological results: compared with the normal group, the volume, weight, anteroposterior diameter, left and right diameter, upper and lower diameters of brain tissue in the model group were decreased, and the difference was statistically significant. The results of HE staining showed that the cortical structure of normal group was clear, stratification was obvious, cells were arranged neatly, and no abnormal neurons were found. In the model group, the absence of corpus callosum, the enlargement of ventricle, the disorder of cortical structure, the disorder of polarity and density of neurons, the abnormal neurons and the nodules in the CA1 area of hippocampus were found in the model group. Conclusion: in this experiment, the MCD rat model was established successfully by the first generation of offspring of female mice irradiated with X ray of 1: 1195cGy. This method is simple and reliable. Rapamycin may decrease the incidence of epileptic waves in middle age MCD rats. Rapamycin has no significant effect on learning and memory ability of middle-aged MCD rats, and has no reverse effect on brain pathological damage.
【学位授予单位】：西南医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R742.1

【参考文献】