IGF-1对全脑缺血大鼠认知功能及p-Akt、p-mTOR蛋白的影响

发布时间：2018-01-12 16:21

本文关键词：IGF-1对全脑缺血大鼠认知功能及p-Akt、p-mTOR蛋白的影响　出处：《川北医学院》2015年硕士论文　论文类型：学位论文

【摘要】：目的:探讨外源性IGF-1对全脑缺血大鼠空间学习记忆能力及对p-Akt、p-m TOR蛋白的影响,进而揭示IGF-1改善全脑缺血大鼠认知障碍的可能机制。方法:将成年雄性Wistar大鼠随机分成正常对照组、假手术组、模型组、IGF-1组、IGF-1+PPP组。对各手术组大鼠行侧脑室置管术,术后第6天,采用改良Pulsinelli四血管阻断法(4-VO)复制全脑缺血模型,假手术组腹腔注射1ml DSMO(PPP溶媒),侧脑室注射NS10ul;模型组腹腔注射1ml DSMO,侧脑室注射NS10ul;IGF-1组腹腔注射1ml DSMO,侧脑室注射IGF-1 10ul(0.2ug/ul);IGF-1+PPP组腹腔注射1ml PPP(20mg/kg,溶于1ml DSMO),侧脑室注射IGF-1 10ul(0.2ug/ul),侧脑室注射晚于腹腔注射30分钟,连续注射7天。于分组前、药物处理7天后分别对各组大鼠行Morris水迷宫实验,水迷宫实验包括定位航行试验和空间探索实验;HE染色观察各组大鼠海马CA1区椎体细胞形态变化;免疫组化法检测各组大鼠海马CA1区p-Akt、p-m TOR蛋白的表达情况,采用Image Pro Plus 6.0软件处理免疫组化图片,统计IOD值,结果用SPSS17.0统计软件进行统计学处理。结果:1)Morris水迷宫实验结果:药物处理7天后,模型组大鼠全时程平均逃避潜伏期较正常组及假手术组延长(p0.05),IGF-1组大鼠全时程平均逃避潜伏期较模型组缩短(p0.05),IGF-1+PPP组大鼠全时程平均逃避潜伏期较IGF-1组延长(p0.05);模型组大鼠跨越原平台次数较正常组及假手术组减少(p0.05),IGF-1组大鼠跨越原平台次数较模型组增多(p0.05),IGF-1+PPP组大鼠跨越原平台次数较IGF-1组减少(p0.05);模型组大鼠在原平台象限游泳时间较正常组及假手术组减少(p0.05),IGF-1组大鼠在原平台象限游泳时间较模型组增多(p0.05),IGF-1+PPP组大鼠在原平台象限游泳时间较IGF-1组减少(p0.05)。2)HE染色结果:模型组海马CA1区细胞较正常组及假手术组排列紊乱,细胞稀疏,细胞核不规则;IGF-1组海马CA1区细胞较模型组排列整齐,结构较清晰,不规则细胞减少。IGF-1+PPP组海马CA1区细胞较IGF-1组排列紊乱,细胞稀疏,细胞核不规则,可见核固缩。3)免疫组化结果:各组均可见p-Akt、p-m TOR阳性表达。模型组海马CA1区阳性表达较正常组及假手术组增多(p0.05);IGF-1组海马CA1区阳性表达较模型组增多(p0.05);IGF-1+PPP组海马CA1区阳性表达较IGF-1组减少(p0.05);模型组及IGF-1+PPP组p-Akt、p-m TOR蛋白阳性表达差异没有统计学意义。结论:1)外源性IGF-1能够改善全脑缺血大鼠空间学习记忆能力。2)外源性IGF-1能够增加全脑缺血大鼠海马CA1区p-Akt、p-m TOR蛋白的表达水平;加用IGF-1受体阻断剂PPP后全脑缺血大鼠海马CA1区p-Akt、p-m TOR蛋白的表达水平较IGF-1组减少。提示IGF-1可能通过促进p-Akt及p-m TOR蛋白的表达,从而改善全脑缺血大鼠空间学习记忆能力。
[Abstract]:Objective: To investigate the effects of exogenous IGF-1 on rat spatial learning and memory ability and cerebral ischemia on p-Akt, P-M TOR protein, and reveal the possible mechanism of IGF-1 in ameliorating cognitive impairment in rats with cerebral ischemia. Methods: adult male Wistar rats were randomly divided into normal control group, sham operation group, model group, IGF-1 group, IGF-1+PPP group. The operation group rats underwent lateral ventricle catheterization, sixth days after operation, by using modified Pulsinelli method four vessels (4-VO) copy the model of whole brain ischemia in sham operation group, intraperitoneal injection of 1ml DSMO (PPP solvent), intracerebroventricular injection of NS10ul; model by intraperitoneal injection of 1ml DSMO, lateral ventricle NS10ul injection; group IGF-1 intraperitoneal injection of 1ml DSMO, intracerebroventricular injection of IGF-1 (0.2ug/ul 10ul); IGF-1+PPP group received intraperitoneal injection of 1ml PPP (20mg/kg, dissolved in 1ml DSMO), intracerebroventricular injection of IGF-1 10ul (0.2ug/ul), 30 minutes after intracerebroventricular injection of intraperitoneal injection, continuous injection of 7 days. Before the group, after treatment for 7 days respectively group of rats by Morris water maze test, positioning navigation test and spatial probe test including water maze test; morphological observation of hippocampal CA1 pyramidal cells in rats with HE staining; immunohistochemistry p-Akt in hippocampal CA1 region of rats, the expression of P-M TOR protein. Using Image Pro Plus 6 software with immunohistochemical images, the statistical value of IOD results with SPSS17.0 statistical software. Results: 1) Morris water maze test results: after treatment for 7 days, the rats in the model group were all Cheng Ping latency than the normal group and sham operation group (P0.05 group), IGF-1 extension rat time average escape latency shortened than that in the model group (P0.05), IGF-1+PPP group rats all duration the average escape latency longer than that of group IGF-1 (P0.05); the rats in the model group compared with the number of times of crossing platform in normal group and sham operation group Reduce (P0.05), IGF-1 group of rats crossing platform times more than model group (P0.05), IGF-1+PPP group of rats crossing platform times lower than that of the IGF-1 group (P0.05); the rats in the model group decreased in the original platform quadrant swimming time than the normal group and sham operation group (P0.05), the rats of group IGF-1 increased in the original platform quadrant swimming time compared to the model group (P0.05), the rats of group IGF-1+PPP decreased in the original platform quadrant swimming time than group IGF-1 (P0.05).2) HE staining: model group hippocampus CA1 cells than in normal group and sham operation group were disordered, sparse, irregular nuclei; IGF-1 group in hippocampus CA1 area compared with the model group, cells arranged orderly, clear structure, irregular cells decreased hippocampal CA1 neurons in.IGF-1+PPP group than in IGF-1 group cells arranged in disorder, sparse, irregular nuclei karyopyknosis.3) immunohistochemical results: each group can see p-Akt, P-M positive expression of TOR in model group sea. The positive expression of horse CA1 area than in normal group and sham operation group (P0.05); the positive expression of IGF-1 group in hippocampus CA1 region increased in comparison with the model group (P0.05 group); the positive expression of IGF-1+PPP in hippocampal CA1 region was lower than IGF-1 group (P0.05); model group and IGF-1+PPP group p-Akt, P-M TOR protein positive expression difference was not statistically significant conclusion: 1) exogenous IGF-1 can improve the ability of learning and memory of.2 space in rats with global cerebral ischemia) exogenous IGF-1 could increase the cerebral ischemia in rats hippocampus CA1 p-Akt, expression of P-M TOR protein; with IGF-1 receptor antagonist PPP after cerebral ischemia p-Akt CA1 of rat hippocampus, the expression level of P-M TOR protein was lower than IGF-1 group. IGF-1 can promote the expression of p-Akt and P-M TOR protein, so as to improve the spatial learning and memory abilities in rats with global cerebral ischemia.

【学位授予单位】：川北医学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R749.13

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