慢性睡眠剥夺对大鼠学习记忆功能及不同脑区5-羟色胺1A受体蛋白表达的影响

目的观察慢性快速眼动相(REM)睡眠剥夺对大鼠学习记忆能力以及海马、前额皮质、下丘脑5-羟色胺1A(5-HT1A)受体蛋白表达变化的影响。方法成年雄性Sprague-Dawley大鼠经过筛选后随机分为空白对照组(BC组,4只)、大平台对照组(TC组,12只)和慢性睡眠剥夺(CSD)组(15只)。采用改良多平台水环境方法建立大鼠慢性REM睡眠剥夺模型,利用Morris水迷宫、自主活动箱检测CSD后大鼠学习记忆功能变化,Western印迹法分析CSD对大鼠海马、前额皮质、下丘脑5-HT1A受体蛋白表达水平的影响。结果自CSD3d起,CSD组大鼠的体重较BC组和TC组显著减轻(P值均<0.01)。在CSD7、14、21d时,CSD组的Morris水迷宫测试潜伏期均显著长于BC组和TC组(P值均<0.01)。从总体趋势看,随着CSD时间的延长,CSD组大鼠Morris水迷宫测试的潜伏期呈现缓慢递增趋势(P值均>0.05)。CSD21d后,CSD组自主活动箱中央区活动速度较TC组显著减慢(P<0.05)。与BC组和TC组相比,CSD21d时CSD组大鼠下丘脑、海马、前额皮质内5-HT1A受体蛋白表达量均显著增加(P值均<0.05),并以下丘脑中增加量最多(P<0.01)。结论慢性REM睡眠剥夺导致大鼠学习记忆能力下降,可能与脑区中5-HT1A受体调节大鼠睡眠有关。

Effect of chronic rapid eye movement sleep deprivation on cognition and protein expression of brain 5-HT1A receptor in rats

Objective To investigate the effect of chronic rapid eye movement (REM) sleep deprivation on learning and memory function and the changes of 5-HT1A receptor protein expression in hippocampus, prefrontal cortex and hypothalamus in rats. Methods Adult male Sprague-Dawley rats were randomly divided into chronic REM sleep deprivation (CSD, n=15), big platform treatment control (TC, n=12) and blank control (BC, n=4) groups after screening experiment. The sleep deprivation model was established by modified multiple platform method. Learning and memory functions were detected by Morris water maze and open field test before and after sleep deprivation. The effects of chronic REM sleep deprivation on 5-HT1A receptor protein expression in the hippocampus, prefrontal cortex and hypothalamus were analyzed by Western blotting analysis. Results Compared with BC and TC groups, the weight of the rats in CSD group was significantly decreased 3 days after sleep deprivation (all P<0.01); on the day 7, 14, 21 after sleep deprivation, the latency for the Morris water maze in CSD group was significantly lengthened (all P<0.01). With the time of sleep deprivation going on, the latency for the Morris water maze increased gradually in CSD rats (P>0.05). Motion speed of the central region in CSD rats was significantly slower than that in TC rats 21 days after CSD (P<0.05). Compared with BC and TC groups, the protein expression of 5-HT1A receptor in the 3 encephalic regions significantly increased in CSD group 21 days after CSD (P<0.05), especially in the hypothalamus (P<0.01). Conclusion Chronic REM sleep deprivation can impair the learning and memory. 5-HT1A receptor may be involved in modulating the dysfunction.