REM期睡眠剥夺对大鼠不同脑区组蛋白H3K9和H3K4甲基化水平的影响

Effect of sleep deprivation on H3K9 and H3K4 methylation in the different brain region of rats

目的:研究REM期睡眠剥夺对成年大鼠不同脑区包括海马、腹内侧前额叶皮质、下丘脑和中缝核群的组蛋白H3K9和H3K4三甲基化水平的影响。方法:将成年SD大鼠随机分为正常对照组(con)、睡眠剥夺1 d组(SD1 d)、睡眠剥夺3 d组(SD3 d)、睡眠剥夺6 d组(SD6 d)。采用改良式多平台水环境法建立REM期睡眠剥夺模型,分别于睡眠剥夺后1、3、6 d断头取脑,用免疫荧光染色与Western Blot检测大鼠海马、腹内侧前额叶皮质、下丘脑和中缝核群H3K9和H3K4三甲基化水平的变化,最终结果进行统计学分析。结果:Western Blot结果显示:(1)海马、腹内侧前额叶皮质三个SD组H3K9三甲基化水平均低于control组(P<0.05),H3K4三甲基化水平均高于control组(P<0.05);(2)下丘脑三个SD组H3K9三甲基化水平均低于control组(P<0.01),但SD1 d组H3K4三甲基化水平高于control组(P<0.05),SD3 d、SD6 d组H3K4三甲基化水平低于control组(P<0.05);(3)中缝核群三个SD组H3K9和H3K4三甲基化水平均高于control组(P<0.05)。对海马与下丘脑免疫荧光验证H3K9三甲基化结果与Western Blot结果趋势一致,且说明细胞无减少。结论:睡眠剥夺可能与海马、腹内侧前额叶皮质、下丘脑和中缝核群的组蛋白H3K9和H3K4三甲基化水平密切相关。

Objective： To observe the effect of sleep deprivation on histone H3 lysine 9 tri-methylation（ H3K9 trime） and histone H3 lysine 4 tri-methylation（ H3K4 trime） in the different brain region containing hippocampus,ventromedia prefrontal cortex,hypothalamus and raphe nuclei of rats. Methods： SD Rats were randomly assigned into four groups： control group,sleep deprivation 1 d group（ SD1 d）,sleep deprivation 3 d group（ SD3 d） and sleep deprivation6 d group（ SD6 d）. The model of sleep deprivation were made by the modified multiple platform technique. The change of tri-methylated H3K9 and H3K4 in hippocampus,ventromedia prefrontal cortex,hypothalamus and raphe nuclei were measured by Western Blot and immunofluorescence,and the final results were analyzed. Results： As detected by Western Blot：（ 1） In hippocampus and ventromedia prefrontal cortex,compared with control group,the level of tri-methylated H3K9 in SD groups decreased significantly,while the level of tri-methylated H3K4 increased（ P〈0. 05）.（ 2） In hypothalamus,there was a decrease in the level of H3K9 tri-methylation in SD groups as compared to control group（ P〈0. 01）,the level of methylated H3K9 increased in the SD1 d group and then decreased in the SD3 d and SD6 d group（ P〈0. 05）.（ 3） In raphe nuclei,the level of tri-methylated H3K9 and H3K4 of SD groups was higher than that ofcontrol group（ P〈0. 05）. The change of H3K9 tri-methylation detected by immunofluorescence in hippocampus and hypothalamus were consistent with the results of Western Blot,and it also indicates that the number of cells did not decrease. Conclusion： The change of tri-methylated H3K9 and H3K4 in hippocampus,ventromedia prefrontal cortex,hypothalamus and raphe nuclei correlate with the detrimental effects of sleep deprivation.