剥夺异相睡眠导致大鼠学习记忆的能力下降的机制

The mechanism of diminishing the ability of learning and memory following paradoxical sleep deprivation in the rats

目的:揭示学习记忆是否会在睡眠中得到加强和巩固,取消异相睡眠是否会导致学习记忆能力下降及其下降的机制。方法:45只雄性Wistar大鼠进行连续4d的Morris水迷宫空间记忆学习任务训练后,立即随机分为剥夺异相睡眠(paradoxicalsleepdeprivation,PSD)、大平台组(TC)、对照组(CC)3组,每组又分为24,48,72h3个亚组,每组各5只。其中所有的PSD组、CC组及TC组在第4天最后1次训练结束后立即分别放入睡眠剥夺箱、大平台水箱和普通鼠笼。24,48和72h后,分别将各组大鼠再次任意选取两个入水点,每个点连续两次寻找平台,来衡量空间参考记忆和空间工作记忆的变化。此时平台所处的位置与学习训练时相同。整个行为学研究过程由水迷宫测试系统记录游泳轨迹和相关参数。结果:①随着训练次数的增加,大鼠逐次各点第1次游泳潜伏期逐渐缩短,记忆得分的值逐渐增大。②PSD各组大鼠与配对的TC组及CC组相比较,其各点第1次游泳潜伏期随PSD时间延长而延长犤72h时为:(88.17±8.75),(22.83±3.98),(22.12±4.95)s,t=15.05,P<0.001犦,记忆得分小于TC,CC组大鼠(72h时为:16.75±4.36,28.15±5.31,30.83±4.97,t=15.05,P<0.001),其差异有显著性意义。TC,CC组大鼠之间其参数统计差异没有显著性意义(P>0.05)。结论:PSD可造成大鼠空间记忆的巩固?

AIM:To reveal the mechanism of diminishi ng the ability of learning and memory following paradoxical sleep deprivation in the rats and to demonstrate the possibility of memory processes and consolidation during paradoxic al sleep(PS)in rats.METHODS:Paradoxical sleep deprivation was p erformed using the'flower pot technique'.Each rat was placed on an inverted'flower pot 'that was just enough(6.5cm in diameter)to hold the animal and was surrounded by water.They fell into the water if their musc le atonia during paradoxical sleep.Controls were either housed in tanks with larg e platforms (TC group)or in normal cages(CC group).All animals had free access to food a nd water throughout the ex-periment.Forty-five male Wistar ra ts were continuously tested in a spat ial learning task using a Morris Water Ma ze for 4d.The rats were set from 4dif-ferent starting points and allowed 2min to find a submerged platform.Two trials were conducted from each starting point.The data(track and parameters)of each rat were recorded and computed a utomatically by Behavioral Analyse s System.At the experimental termination on the 4th day,all animals were d i-vided into 3groups randomly:24-hou r group(PSD 24 ,n=5;TC 24 ,n=5;and CC 24 ,n=5),48-hour group(PSD 48 ,n=5;TC 48 ,n=5;and CC 48 ,n=5)and72-hour group(PSD 72 ,n=5;TC 72 ,n=5;and CC 72 ,n=5).RESULTS:①The latency was significantly shortened and the scores of memory acquisition were increased d uring the first swimming along with t he increased times of trial.②The latency of PSD group was(8817±8.75)s at72hours,significantly longer than that of the TC group and CC group(22.83±3.98)s and(22.12±4.95)s(t=15.05,P<0.001).The scores of memory were 16.75±4.36for the PSD group at 72hours,signifi-cantly lower than those of the other g roups(28.15±5.31,30.83±4.97)(t=15.05,P<0.001).There was no significant difference between the TC group and CC group(P>0.05).