两种小鼠恐惧记忆形成的差异与血皮质醇水平及海马CA1区NMDA受体亚单位表达的关系
发布时间：2018-12-09 13:56
【摘要】： 目的通过建立小鼠恐惧记忆能力的实验动物模型，探索恐惧记忆形成后海马CA1区NMDA受体亚单位表达的变化，从而寻找其分子作用机制。 方法选用昆明种(KM)和C57BL／6小鼠，将足底电击刺激的训练与声音相结合，观察同一品种小鼠用不同电击强度以及不同品种小鼠用相同条件训练时，恐惧性记忆建立的差异。以训练后24 h测试时出现木僵反应(stupor response)，作为恐惧性记忆形成的表现。以Flou-3／AM作为荧光探针，用同源共聚焦显微镜测定脑片和培养海马神经细胞内钙离子浓度变化；取脑组织，冷冻切片，用免疫组化方法测定海马CA1区NMDA受体亚单位及c-fos表达，高效液相色谱法测定血浆皮质酮水平，将以上结果与行为学结果进行相关性分析。 结果将声音分别结合0.4mA、0.6mA、0.9mA足底电击，24 h后在KM小鼠引出的木僵反应时间分别为60.00±57.77s，110.00±129.61s，101.99±20.38s，强度0.6mA组的合格率最高(30％)，组间比较无显著性差异(P＞0.05)。C57BL／6小鼠在声音结合0.4mA电击条件下，木僵反应时间为275.62±36.99s，显著长于KM小鼠的时间(P＜0.01)，其合格率为100％，远高于KM小鼠的7.69％(0.4mA)。KM小鼠对照组和训练组血浆皮质酮水平分别为(101.083±70.266)μg/L、(215.453±60.276)μg/L，两者比较差异显著(P＜0.01)；训练组血浆皮质酮水平与训练结果木僵反应时间(36.00±29.292)s之间无相关性(r=-0.273，P＞0.05)。C57BL／6小鼠对照组和训练组血浆皮质酮水平分别为(108.009±20.452)μg/L、(176.933±38.202)μg/L，两者比较差异显著(P＜0.01)；训练组血浆皮质酮水平与训练结果木僵反应时间(257.50±36.450s)之间无相关性(r=-0.462，P＞0.05)。两种小鼠的对照组、训练组比较，均为P＞0.05，差异无显著性意义。 C57BL／6小鼠训练组海马组织CA1区神经细胞c-fos表达水平明显高于对照组(P＜0.05)，前者阳性细胞数平均值为185.18±31.131，后者为145.39±54.383；前者平均灰度值为12583.02±3543.554，后者为8436.851±3434.484，两者比较差异有统计学显著意义(P＜0.01)。NR2B的检测，阳性细胞数平均值训练组为(287.75±19.992)、对照组为(254.26±31.897)，两者比较差异有统计学显著意义(P＜0.01)；前者平均灰度值为47703.90±11152.912，，后者为39009.06±11586.680，两者比较差异有统计学显著意义(P＜0.05)。 结论①C57BL／6小鼠在声音70dB，0.4mA电刺激下，24h后恐惧木僵反应时间满足实验要求，成功率达95％以上；②血浆皮质酮水平与训练成绩无明显相关性，但C57BL／6小鼠相关系数r为-0.462，|r|大于0.3，小于0.5，呈低度负相关。两种小鼠训练前后血浆皮质酮水平无明显差异，训练效果的差异与激素水平高低无关；是否遗传背景的差异影响记忆保持的分子机制，有待进一步研究；③海马CA1区神经元在恐惧记忆形成后，NR2B、c-fos表达明显增多，提示应激时血浆内皮质酮浓度升高，可能通过细胞内基因表达增强，引起海马CA1脑区LTP的易化和固化，从而使恐惧记忆得以较长时间保留。
[Abstract]:Objective To study the changes of the expression of NMDA receptor subunits in the CA1 region of the hippocampus after the formation of the fear memory by establishing an experimental animal model of the mouse's fear and memory ability. Methods Kunming (KM) and C57BL/ 6 mice were selected to combine the training and the sound of the stimulation of the electric shock of the sole. The difference between memory and memory was recalled. The post-training 24-hour test showed a stupor response as a memory of fear. The changes of calcium ion concentration in the brain and the cultured hippocampal neurons were measured by using Flou-3/ AM as a fluorescent probe, and the concentration of calcium in the neurons of the hippocampus was measured by using a homologous confocal microscope. The NMDA receptor subunits and c in the CA1 region of the hippocampus were determined by immunohistochemistry.-fos expression, high performance liquid chromatography to measure the plasma corticosterone level, and the above results are compared with the behavior results. The results showed that the reaction time was 60. 00, 57. 77s, 110. 00, 129. 61s, 101. 99, 20. 38s, and the intensity of 0. 6mA group was the highest (30%) after 24 h, respectively. There was a significant difference (P> 0.05). In C57BL/ 6 mice, the reaction time was 275.62-36.99s, which was significantly longer than that of KM mice (P <0.01). The qualified rate was 100%, which was much higher than that of KM mice (P <0.01). The levels of plasma corticosterone in the control group and the training group of KM mice were (101.08). 3 (70. 266). mu. g/ L, (215. 453, 60. 276). mu. g/ L, the difference was significant (P <0.01), and there was no correlation between the level of plasma corticosterone in the training group (36. 00-292.292) s (r =-). The levels of the plasma corticosterone in the control group and the training group of the C57BL/ 6 mice were (108.009-20.452) and (176.933-382.202). m/ L, respectively (P <0.01), and the plasma corticosterone levels in the training group were compared with the training results (257.50-360.450s). No correlation (r =-The control group and the training group of the two mice were P> The expression of c-fos in the hippocampal tissue of the training group of C57BL/ 6 mice was significantly higher than that in the control group (P <0.05). The average positive cell number was 185.18-31.131, the latter was 145.39-543.383; the average gray-scale value of the former was 12583.02-3543. 554, the latter being 8436,851, 3434. 484, both The difference was statistically significant (P <0.01). The mean value of the positive cells was (282875-19.992), and the control group was (252.26-31.897), and the difference was statistically significant (P <0.01). The average gray-scale value of the former was 47703. 90-11152.912. The person is 39009. 06/ 11586. 680, both Conclusion The results showed that in C57BL/ 6 mice, the reaction time of fear wood after 24 h was higher than 95% after 24 h under the electric stimulation of 70dB and 0.4mA. However, the level of corticosterone in plasma was not related to the results of training, but C57 The correlation coefficient r of BL/ 6 mice was-There was no significant difference in plasma corticosterone levels before and after training in both mice. The difference of the training effect was not related to the level of the hormone. The expression of NR2B and c-fos increased significantly after the formation of the fear and memory in the CA1 region of the hippocampus, suggesting that the concentration of the corticosterone in the plasma during the stress could be enhanced by the expression of the gene in the cells, causing the CA1 of the hippocampus.
【学位授予单位】：青岛大学
【学位级别】：硕士
【学位授予年份】：2007
【分类号】：R338
本文编号：2369469
[Abstract]:Objective To study the changes of the expression of NMDA receptor subunits in the CA1 region of the hippocampus after the formation of the fear memory by establishing an experimental animal model of the mouse's fear and memory ability. Methods Kunming (KM) and C57BL/ 6 mice were selected to combine the training and the sound of the stimulation of the electric shock of the sole. The difference between memory and memory was recalled. The post-training 24-hour test showed a stupor response as a memory of fear. The changes of calcium ion concentration in the brain and the cultured hippocampal neurons were measured by using Flou-3/ AM as a fluorescent probe, and the concentration of calcium in the neurons of the hippocampus was measured by using a homologous confocal microscope. The NMDA receptor subunits and c in the CA1 region of the hippocampus were determined by immunohistochemistry.-fos expression, high performance liquid chromatography to measure the plasma corticosterone level, and the above results are compared with the behavior results. The results showed that the reaction time was 60. 00, 57. 77s, 110. 00, 129. 61s, 101. 99, 20. 38s, and the intensity of 0. 6mA group was the highest (30%) after 24 h, respectively. There was a significant difference (P> 0.05). In C57BL/ 6 mice, the reaction time was 275.62-36.99s, which was significantly longer than that of KM mice (P <0.01). The qualified rate was 100%, which was much higher than that of KM mice (P <0.01). The levels of plasma corticosterone in the control group and the training group of KM mice were (101.08). 3 (70. 266). mu. g/ L, (215. 453, 60. 276). mu. g/ L, the difference was significant (P <0.01), and there was no correlation between the level of plasma corticosterone in the training group (36. 00-292.292) s (r =-). The levels of the plasma corticosterone in the control group and the training group of the C57BL/ 6 mice were (108.009-20.452) and (176.933-382.202). m/ L, respectively (P <0.01), and the plasma corticosterone levels in the training group were compared with the training results (257.50-360.450s). No correlation (r =-The control group and the training group of the two mice were P> The expression of c-fos in the hippocampal tissue of the training group of C57BL/ 6 mice was significantly higher than that in the control group (P <0.05). The average positive cell number was 185.18-31.131, the latter was 145.39-543.383; the average gray-scale value of the former was 12583.02-3543. 554, the latter being 8436,851, 3434. 484, both The difference was statistically significant (P <0.01). The mean value of the positive cells was (282875-19.992), and the control group was (252.26-31.897), and the difference was statistically significant (P <0.01). The average gray-scale value of the former was 47703. 90-11152.912. The person is 39009. 06/ 11586. 680, both Conclusion The results showed that in C57BL/ 6 mice, the reaction time of fear wood after 24 h was higher than 95% after 24 h under the electric stimulation of 70dB and 0.4mA. However, the level of corticosterone in plasma was not related to the results of training, but C57 The correlation coefficient r of BL/ 6 mice was-There was no significant difference in plasma corticosterone levels before and after training in both mice. The difference of the training effect was not related to the level of the hormone. The expression of NR2B and c-fos increased significantly after the formation of the fear and memory in the CA1 region of the hippocampus, suggesting that the concentration of the corticosterone in the plasma during the stress could be enhanced by the expression of the gene in the cells, causing the CA1 of the hippocampus.
【学位授予单位】：青岛大学
【学位级别】：硕士
【学位授予年份】：2007
【分类号】：R338
【参考文献】
相关期刊论文 前4条
1 陈鹏慧,阮怀珍,吴喜贵;缺氧及谷氨酸对大鼠下丘脑神经元NMDA通道的影响[J];第三军医大学学报;2001年04期
2 孙臣友;戚双双;陈朝玉;刘能保;张敏海;;皮质酮对原代培养的海马神经元及其[Ca~(2+)]_i和钙/钙调蛋白依赖性蛋白激酶Ⅱ表达的影响[J];解剖学杂志;2006年03期
3 嵇志红,邹伟;应激对大鼠学习和记忆的影响[J];中国行为医学科学;2002年01期
4 李爱萍,赵慧,李韶,朴花,孙长凯;不同鼠种在Morris水迷宫学习记忆行为中的种属差异[J];中国行为医学科学;2005年01期
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