睡眠剥夺引起大鼠海马神经元凋亡与丝裂素活化蛋白激酶表达的变化

背景:丝裂素活化蛋白激酶是一组与神经元的存活凋亡有关的蛋白激酶,睡眠剥夺可以引起神经元凋亡。目的:观察睡眠剥夺大鼠丝裂素活化蛋白激酶表达的变化并分析其可能的意义。设计:完全随机分组的前瞻性研究。单位:郑州大学生理学教研室神经研究室。材料:实验于2000-06/2002-10在郑州大学完成。选取成年健康SD大鼠24只。方法:24只大鼠随机分为快眼动睡眠剥夺组、快眼动睡眠剥夺对照组和正常对照组3组,每组8只。睡眠剥夺组从早晨8点始,连续剥夺睡眠72h。正常对照组则置饲养笼中饲养,维持正常的睡眠-觉醒周期。观察其形态学变化。另取24只大鼠分组同上用于丝裂素活化蛋白激酶的检测。采用TUNEL染色法观察睡眠剥夺大鼠的海马神经元形态学变化,观察细胞外信号调节激酶活性的变化和c-Jun氨基末端激酶蛋白表达量的变化。主要观察指标:①观察睡眠剥夺大鼠海马神经元的形态学变化。②观察海马神经元细胞外信号调节激酶和c-Jun氨基末端激酶表达的变化。结果:①海马神经元形态学变化:快眼动睡眠剥夺组大鼠CA1和CA3区可见较多的凋亡阳性细胞,主要分布在海马的锥体细胞层。CA2区仅见极少量凋亡细胞,CA4区偶见凋亡细胞。正常对照组和快眼动睡眠剥夺对照组海马组织切片中未见明显阳性细胞。②细胞外信号调节激酶活性的变化:快眼动睡眠剥夺组明显低于快眼动睡眠剥夺对照组和对照组(1764.00±941.56,6139.67±2863.62,566.700±2763.41,t=3.2111,0.9863,P<0.05)。③c-Jun氨基末端激酶的阳性表达:快眼动睡眠剥夺组明显高于快眼动睡眠剥夺对照组和对照组(87.5%,25%,75%,t=3.4121,P<0.05)。结论:睡眠剥夺可引起大鼠海马神经元丝裂素活化蛋白激酶活性的变化,可能与神经元的凋亡有关。

Apoptosis in hippocampal neurons and change of mitogen-activated protein kinases expression in rats with sleep deprivation

BACKGROUND: Mitogen-activated protein kinases (MAPKs) is a group of protein kinase related with neuronal apoptosis. Sleep derivation can lead to neuronal apoptosis.OBJECTIVE: To observe change and possible significance of MAPKs in rats after sleep deprivation.DESIGN: Prospective study with complete randomization.SETTING:Research Room of Nerve, Department of Physiology, Zhengzhou University.MATERIALS: The experiment was performed at Zhengzhou University from June 2000 to October 2002. Totally 24 adult healthy SD rats were selected.METHODS: A total of 24 rats were randomly assigned into rapid eye movement (REM) sleep deprivation group, REM sleep deprivation control group and normal control group with 8 rats in each group. The rats in the sleep deprivation group received successive sleep deprivationfor 72 hours from 8:00in the morning. The rats in the normal control group were fed in the rearing cage, having normal sleep-awareness cycle. Their morphological change was observed. Another 24 rats were grouped as above and determined with MAPKs. Morphological change of neurons in hippocampus of rats after sleep deprivation was observed with terminal dUTP nick end-labelling (TUNEL)staining. Changes of activity of extracellular signal-regulated kinase (ERK)and expression of c-Jun N-terminal kinase (JNK) were observed.MAIN OUTCOME MEASURES: ①Morphological change of hippocampal neuron in rats after sleep derivation was observed. ②Changes of expressions of ERK and JNK in hippocampal neuron were observed.RESULTS: ①Morphological change of hippocarnpal neuron: A mass of apoptotic positive cells appeared in CA1 and CA3 regions of rats in the REM sleep deprivation group, mainly distributed in pyramidal layer of hippocampus. A few apoptotic cells appeared in CA2 region. Seldom apoptotic cells appeared in the CA4 region. There was no significant positive cell in hippocampal tissue sections of the normal control group and REM sleep deprivation control group. ②Change of ERK activity: It was significantly lower in the REM sleep deprivation group than the REM sleep deprivation control group and normal control group (1 764.00±941.56,6 139.67±2 863.62,566.700±2 763.41 ,t=3.211 1,0.986 3,P ＜ 0.05). ③JNK positive expression: It was markedly higher in the REM sleep deprivation group than the REM sleep deprivation control group and normal control group (87.5%, 25%, 75%, t=3.412 1, P＜0.05).CONCLUSION: The sleep deprivation can cause change of MAPKs activity, which may be related with neuron apoptosis.