睡眠剥夺引起大鼠海马神经元凋亡及相关基因表达的变化

背景:睡眠剥夺是否引起细胞变性,其信号传导是否与某些基因调控有关。目的:探讨睡眠剥夺引起的神经元凋亡与相关基因表达的变化。设计:随机对照实验研究。地点和材料:实验地点:郑州大学医学院生理学实验室。成年健康SD大鼠,雌雄不限,体质量(200±20)g,由河南省实验动物中心提供。干预:采用TUNEL染色观察了快眼动睡眠剥夺大鼠海马神经元形态学变化,应用原位杂交检测了快眼动睡眠剥夺大鼠海马bcl-2,baxmRNA表达。主要观察指标:睡眠剥夺大鼠海马神经元形态学变化;海马bcl-2和baxmRNA表达。结果:快眼动睡眠剥夺大鼠海马CA1,CA3区神经元阳性凋亡细胞数增多,异相睡眠剥夺组海马CA1～CA4区细胞凋亡率分别为(6.60±2.24)%,(1.69±0.45)%,(6.87±1.32)%,(1.74±0.98)%。CA1,CA3区细胞凋亡率和CA2,CA4区相比较差异有显著性意义(t=5.26～6.95,P<0.05)。bcl-2mRNA阳性信号表达积分值较强,四个区之间差异无显著性意义,baxmRNA表达增强犤CA1为(211.12±59.85);CA3为(205.56±56.99)犦与CA2和CA4区犤(123.42±22.80),(124.21±20.47)犦比较差异有显著性意义(t=3.20～4.36,P<0.05)。结论:睡眠剥夺可引起大鼠海马神经元凋亡,与凋亡相关的bcl-2,baxmRNA基因表达的变化可能涉及神经元的凋亡机制。

Neuronal apoptosis in hippocampus of rats caused by sleep deprivation and changes coordinated gene expression

BACKGROUND: To make sure whether sleep deprivation will cause cell degeneration and if its signal conduction is related to expressions of certain genes.OBJECTIVE: To explore the apoptosis of neutrons caused by sleep deprivation as well as the expressive changes of related genes.DESIGN: Randomized case controlled study.SETTING and MATERIALS: Experimental site: Physiological Laboratory of School of Medicine, Zhengzhou University. Adult SD rats provided by Experimental Animal Center of Henan Province which weighed about (200 ± 20) g were chosen of either sex.INTERVENTIONS: TUNEL dyeing method was used to observe the morphologic changes of neurons in hippocampus of rats caused by rapid eye movement sleep deprivation. The expressions of mRNA of bcl-2 and bax in hippocampus of rats were detected by in situ hybridization.MAIN OUTCOME MEASURES: The morphologic changes of neurons in hippocampus of rats caused by sleep deprivation; expressions of mRNA of bcl-2 and bax in hippocampus.RESULTS: The number of positive apoptosis neurons in CA1, CA3 regions of hippocampus in rats was increased after rapid eye movement sleep deprivation. The apoptosis rates of cells in CA1 to CA4 regions in hippocampus caused by paradoxical sleep deprivation were(6.60 ±2.24)% ,(1.69 ±0. 45)% , (6. 87 ± 1.32)% and (1.74 ±0. 98)% respectively.There was significant difference between the apoptosis rates of CA1, CA3 regions and CA2, CA4 regions( t =5.26 -6.95, P ＜0. 05). The value of positive signal expressions of bcl-2 mRNA was much stronger without different between four regions. The expression of bax mRNA was increased, there was difference between the expressions of CA1(211.12 ±59. 85), CA3(205.56 ±56.99)and CA2 ( 123.42 ± 22.80), CA4 ( 124. 21 ± 20.47 ) ( t = 3.20 - 4.36,P ＜ 0.05).CONCLUSION: Sleep deprivation can lead to neuronal apoptosis in hippocampus of rats. The expressive changes of mRNA of bcl-2 and bax may be the mechanism of neuron apoptosis.