孕期尼古丁暴露对大鼠成年子代学习记忆能力的影响及其机制

发布时间：2018-04-12 13:39

本文选题：古丁 + 子代　；参考：《苏州大学》2014年硕士论文

【摘要】：第一部分孕期尼古丁对大鼠子代脑发育的影响 1.1目的：研究孕期母鼠暴露于尼古丁对胎鼠及成年子代脑发育的影响。 1.2方法：将妊娠母鼠随机分为对照组和尼古丁组，每组16只；两组分别于妊娠第四天（GD4）,4%水合氯醛麻醉后，于大鼠颈背部置入微量缓释泵。尼古丁组置入每天以6mg/kg速度释放尼古丁的微量缓释泵,对照组置入装有生理盐水的微量缓释泵。两组各取8只孕鼠，在GD21时用4%水合氯醛麻醉，取出胎鼠称量体重后，暴露胸腔心脏穿刺收集胎鼠血液，然后断头取脑，称量大脑重量。使用血气分析仪检测胎鼠血气指标及电解质水平；用渗透压仪检测血浆渗透压。两组剩余孕鼠自然分娩，，子代标准化饲养至成年（五个月），用4%水合氯醛麻醉，称量其体重；腹主动脉取血后断头取脑，称量大脑重量。用血气分析仪检测成年子代血气指标及电解质水平；用渗透压仪检测血浆渗透压。 1.3结果：尼古丁组GD21胎鼠的体重及大脑重量与对照组相比显著下降（P＜0.05）；尼古丁组胎鼠血液中血氧分压、血氧饱和度明显降低（P＜0.05），血二氧化碳分压、血红蛋白含量明显升高（P＜0.05）,血浆渗透压、血钠水平、血钾水平没有显著差异（P＞0.05）。检测尼古丁组成年子代大鼠上述指标与对照组相比没有显著差异（P＞0.05）。结论：孕期尼古丁暴露对GD21胎鼠脑发育及血气指标产生了一定影响。第二部分孕期尼古丁对大鼠成年子代学习记忆的影响 2.1目的：研究孕期尼古丁对大鼠成年子代学习记忆的影响及其机制。 2.2方法：将妊娠母鼠随机分成对照组和尼古丁组，建模方法同第一部分。两组大鼠自然分娩后，子代标准化饲养至成年（五个月）用于实验。1)用Morris水迷宫方法，观察对照组、尼古丁组的大鼠成年子代学习记忆能力；2)用Real-Time PCR方法检测两组大鼠成年子代海马脑区N-甲基-D-天门冬氨酸受体的1型亚基（NR1）、α7型烟碱型乙酰胆碱受体（α7nAChR）基因的表达；3）使用Western blot方法检测其成年子代大鼠海马脑区NR1、α7nAChR、毒蕈碱受体（M）蛋白的表达。 2.3结果：1）尼古丁组成年子代的学习记忆能力与对照组相比显著下降（P＜0.05）；2)尼古丁组成年子代大鼠海马脑区NR1基因表达与对照组相比明显升高（P＜0.05），α7nAChR基因表达与对照组相比无明显差异（P＞0.05）；3）尼古丁组成年子代大鼠海马脑区NR1蛋白表达与对照组相比明显升高（P＜0.05），α7nAChR蛋白表达与对照组相比明显下降（P＜0.05）； M1、M3、M5受体蛋白表达与对照组相比无明显差异（P＞0.05）。结论:孕期尼古丁组大鼠成年子代学习记忆能力与对照组相比显著下降；且尼古丁组成年子代大鼠海马脑区NR1基因和蛋白的表达量显著升高；α7nACh受体基因表达无明显差异，α7nACh受体蛋白表达显著下降； M1、M3、M5受体蛋白表达与对照组相比无显著差异，提示孕期尼古丁暴露可能导致大鼠成年子代海马区NMDA受体和胆碱能相关受体基因和蛋白的表达发生改变并与成年子代学习记忆能力受损有一定相关性。
[Abstract]:The effect of nicotine on the development of rat offspring during pregnancy

Objective : To study the effects of exposure of pregnant female rats on the development of fetal and adult offspring .

1.2 Methods : Pregnant female rats were randomly divided into control group and nicotine group , 16 rats in each group ;
A micro - sustained - release pump was placed on the back of the rat ' s neck after the fourth day of gestation ( GD4 ) and 4 % water chloral hydrate .
The osmotic pressure of plasma was measured by osmotic pressure instrument . Two groups of residual pregnant rats were given natural labor , and the offspring was standardized to feed to adult ( five months ) .
Blood gas analyzer was used to measure the blood gas index and electrolyte level of adult offspring .
The osmotic pressure of plasma was measured by osmotic pressure instrument .

1.3 Results : Body weight and brain weight of GD21 fetal mice were significantly lower than those in control group ( P < 0.05 ) .
There was no significant difference in blood oxygen partial pressure , blood oxygen saturation ( P < 0 . 05 ) , plasma osmotic pressure , serum sodium level and potassium level in the blood of rats with nicotine group ( P < 0 . 05 ) .

Effect of second part of pregnancy nicotine on learning and memory of adult offspring in rats

Objective : To study the effect of nicotine on learning and memory of adult offspring in rats and its mechanism .

2.2 Methods : The pregnant female rats were randomly divided into control group and nicotine group , the modeling method was the same as that of the first part . After natural labor in the two groups of rats , the filial generation standardized feeding to adult ( five months ) was used in the experiment . 1 ) The learning and memory ability of adult offspring in the control group and nicotine group was observed by Morris water maze method .
2 ) The expression of N - methyl - D - aspartate receptor type 1 subunit ( NR1 ) and 伪7 nicotinic acetylcholine receptor ( 伪7nCR ) gene was detected by Real - Time PCR ( Real - Time PCR ) .
3 ) Western blot was used to detect the expression of NR1 , 伪7nCR , muscarinic receptor ( M ) protein in the hippocampus of adult offspring rats .

2 . Results : 1 ) The learning and memory ability of nicotine group decreased significantly compared with the control group ( P < 0.05 ) .
2 ) Compared with the control group , the expression of NR1 gene in the hippocampus of the rat hippocampus was significantly higher than that in the control group ( P < 0.05 ) .
3 ) Compared with the control group , the expression of NR1 protein in the hippocampus of the rat hippocampus was significantly higher than that in the control group ( P < 0.05 ) .
There was no significant difference between the expression of M1 , M3 and M5 receptor protein compared with the control group ( P > 0.05 ) .
and the expression quantity of NR1 gene and protein in the hippocampus brain region of the rat hippocampus in the composition year of nicotine is obviously increased ;
There was no significant difference in the expression of 伪7nach receptor gene , and the expression of 伪7nach receptor protein decreased significantly .
There was no significant difference between the expression of M1 , M3 and M5 receptor protein compared with the control group , suggesting that the exposure of nicotine in pregnancy could lead to a change in the expression of NMDA receptor and cholinergic receptor gene and protein in the hippocampus of the adult offspring of rats and to be related to the impairment of the learning and memory ability of the adult offspring .

【学位授予单位】：苏州大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R714.7

【参考文献】