组织激肽释放酶8在宫内生长受限大鼠海马中的表达及其意义

发布时间：2018-01-03 02:38

本文关键词：组织激肽释放酶8在宫内生长受限大鼠海马中的表达及其意义　出处：《苏州大学》2012年硕士论文　论文类型：学位论文

【摘要】：目的：用孕期全程低蛋白（6%）饮食法制造宫内生长受限（Intrauterine growthretardation,IUGR）仔鼠脑损伤模型，观察组织激肽释放酶8（Neuropsin，KLK8）在海马中的表达变化，检测仔鼠学习记忆能力，探讨IUGR发生脑损伤的机制。方法：选取健康三月龄Sprague-Dawley大鼠28只，按照雌雄1：1的比例置于同一笼中交配。受孕成功的孕鼠随机分为对照组和IUGR组。对照组母鼠自受孕后第一天开始给予21%正常蛋白饮食，而IUGR组母鼠自受孕后第一天开始给予6%低蛋白饮食，建立IUGR仔鼠模型。两组仔鼠生后至21日的哺乳期内，均给予母鼠21%正常蛋白饮食喂养、自由饮水。21日后将母鼠与仔鼠分笼，给予两组仔鼠21%正常蛋白饮食喂养、自由饮水，喂养至32日。选择1日、5日、10日和21日作为观察的4个时间点，每个时间点每组有6只仔鼠，测量仔鼠体重、头臀长、脑湿重，并对各个时间点仔鼠留取海马组织，HE染色观察1日及21日海马结构的变化，用Westernblot检测海马组织中组织激肽释放酶8的表达，于26日至32日行Morris水迷宫测试，检测仔鼠学习记忆能力。结果：1、两组仔鼠体格生长及脑重的动态比较：与对照组相比，1日龄IUGR仔鼠形态瘦小，体重、头臀长及脑湿重均降低（P＜0.05）；5日龄及10日龄时体重、头臀长及脑湿重仍落后（P＜0.05）；经追赶生长，到21日龄时，体重、头臀长无明显差异（P＞0.05），脑湿重仍低（P＜0.05）。 2、两组仔鼠海马HE染色的变化：与对照组相比，1日龄时IUGR仔鼠海马神经元细胞排列疏松、紊乱，细胞数目减少；部分细胞水肿明显，出现空泡；核固缩细胞比较多，出现凋亡细胞。21日龄时IUGR组神经元细胞水肿基本消失，但细胞排列仍相对疏松、紊乱，细胞数目未见明显增多。 3、两组仔鼠海马中组织激肽释放酶8的表达：在四个时间点，1日龄时两组仔鼠组织激肽释放酶8的表达低，5日龄时两组仔鼠组织激肽释放酶8的表达增加，10日龄和21日龄时两组仔鼠组织激肽释放酶8的表达急剧增加；与对照组相比，，在四个时间点， IUGR仔鼠组织激肽释放酶8的表达均低于对照组（P＜0.05）。 4、Morris水迷宫实验显示：（1）两组仔鼠逃避潜伏期于测试第1天至第5天逐渐缩短；第5天IUGR组逃避潜伏期明显长于对照组，具有统计学意义（P0.05）。（2）搜寻策略结果：第5天时，IUGR组和对照组成绩比较有差异，具有统计学意义（P0.05）。（3）两组穿越平台次数无明显差异（P0.05）。结论：1、用6%低蛋白饮食法能建立IUGR大鼠脑损伤模型。 2、IUGR仔鼠体态瘦小，脑重低，海马神经元细胞数目少。给予IUGR仔鼠正常喂养，体格上可实现追赶生长，但脑重、神经元数目仍落后于正常仔鼠，并且出现学习能力的降低。 3、IUGR仔鼠组织激肽释放酶8在海马中的表达量一直低于正常组仔鼠，组织激肽释放酶8表达的下降可能是IUGR发生脑损伤的机制之一。
[Abstract]:Objective: to produce intrauterine growthretardation with intrauterine growth restriction (ICGR) by using a diet with low protein content during pregnancy. The brain injury model of IUGR-based rats was used to observe the expression of KLK8 in hippocampus and the ability of learning and memory. To explore the mechanism of brain injury in IUGR. Methods: 28 healthy three-month-old Sprague-Dawley rats were selected. The pregnant mice were randomly divided into control group and IUGR group according to the ratio of male and female 1: 1. The control group was given 21% normal protein diet from the first day after conception. In IUGR group, the female rats were given 6% low-protein diet from the first day after conception to establish the IUGR rat model. The two groups were breast-feeding from postnatal to 21st. All rats were fed with 21% normal protein diet. After free drinking, the rats were divided into cages and fed with 21% normal protein diet for 32 days. Choose 1st. Four time points were observed on 5th, 10th and 21st. There were 6 rats in each group at each time point. The body weight, length of head and hip, brain wet weight were measured, and hippocampal tissue was retained at each time point. The changes of hippocampal structure in 1st and 21st were observed by HE staining, and the expression of kallikrein 8 in hippocampus was detected by Westernblot. Morris water maze test was performed from 26th to 32 to test the learning and memory ability of young mice. Results compared with the control group, the body growth and brain weight of the two groups were compared with those of the control group. Compared with the control group, the body weight, body weight, head and hip length and brain wet weight of 1-day-old IUGR rats were decreased (P < 0.05). At 5 and 10 days of age, the body weight, the length of head and hip and the wet weight of brain still lagged behind (P < 0.05). At 21 days of age, there was no significant difference in body weight and length of head and hip (P > 0.05), and the brain wet weight was still low (P < 0.05). 2, the changes of HE staining in hippocampus of the two groups: compared with the control group, the hippocampal neurons of IUGR rats were loosely arranged, disordered and the number of cells decreased at 1 day old compared with the control group. Some of the cells showed obvious edema and vacuoles. There were many pyknotic cells in the nucleus. The edema of neurons in the IUGR group disappeared basically at the age of 21 days, but the arrangement of the cells was still relatively loose and disordered, and the number of the cells did not increase significantly. 3, the expression of kallikrein 8 in hippocampus of the two groups: the expression of kallikrein 8 was low at the age of 1 day at four time points. The expression of kallikrein 8 in the tissues of the two groups increased sharply at the age of 5 days and 21 days, respectively, and the expression of kallikrein 8 increased sharply at the age of 10 days and 21 days of age, and the expression of kallikrein 8 in the tissues of the two groups increased sharply. Compared with the control group, the expression of kallikrein 8 in the tissues of IUGR rats was lower than that of the control group at four time points (P < 0.05). (4) Morris water maze test showed that the escape latency of the two groups was shortened from the first day to the fifth day. On the 5th day, the escape latency of IUGR group was significantly longer than that of control group, with statistical significance (P 0.05). The result of search strategy: on the 5th day, there were differences between IUGR group and control group. There was no significant difference in the frequency of crossing the platform between the two groups. Conclusion the brain injury model of IUGR rats can be established by 6% low protein diet. 2IUGR mice were small in body, low in brain weight, and few in the number of hippocampal neurons. Given normal feeding to the IUGR offspring, they could catch up and grow physically, but the brain was heavy. The number of neurons still lagged behind that of normal mice, and the learning ability decreased. 3The expression of kallikrein 8 in hippocampus of pups with IUGR was lower than that of normal rats, and the decrease of expression of kallikrein 8 might be one of the mechanisms of brain injury in IUGR.
【学位授予单位】：苏州大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R341

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