REM睡眠剥夺对大鼠额叶皮质磷酸化eIF2α表达的影响

Rapid eye movement sleep deprivation on expression of phospho-elF2α in rat frontal cortex

目的观察不同时间的快速眼动(REM)睡眠剥夺对大鼠额叶皮质磷酸化真核翻译起始因子(elF2α)蛋白表达的影响。方法采用改良多平台睡眠剥夺法,将Sprague-Dawle大鼠分为6h、12h、24h和72h时间段进行REM期睡眠剥夺。采用免疫组织化学方法和蛋白质免疫印迹(Western blot)技术观察REM睡眠剥夺后大鼠额叶磷酸化eIF2α蛋白表达的分布特点和变化规律。结果免疫组化观察到eIF2α(P)免疫反应阳性表达在睡眠剥夺6h开始增多,12h、24h显著增多,72h降低,阳性指数分别为80.733±4.094、121.288±3.453、106.197±6.611、67.890±4.173;Western blot实验发现,与对照组相比,REM睡眠剥夺早期大鼠额叶皮质激活了磷酸化的eIF2α,在12h(1.103±0.200)达到高峰,并持续到24h(1.095±0.157),睡眠剥夺72h(0.566±0.074)后逐渐下降。结论短期REM睡眠剥夺能诱导大鼠额叶皮质磷酸化eIF2α蛋白表达,使蛋白合成抑制。

Objective To observe the changes of phosphorylation of the alpha subunit of eukaryotic initiation factor 2（eIF2α（p））protein expression in the rat cerebral codex at different stages of rapid eye movement sleep deprivation（SD）.Methods The modified multiple platform methods（MMPM）were established as the rapid eye movement（REM）sleep deprivation method.The SD animals were sacrificed at the end of 6,12,24,and 72 h SD periods respectively.Immunohistochemistry and Western blot were used to detect the expression and distribution of eIF2α（P）in the rats frontal cortex.Results Immunohistochemistry results showed that the eIF2α（P）positive brown staining localized in the cytoplasmic of cortex neurons.Compared to control group,western blot results showed that the expression of eIF2α（P）in cerebral cortex increased after early SD and reached a peak at 12 h,and lasted until 24 h（1.095±0.157）,then decreased gradually after SD 72 h（0.566±0.074）.Conclusions Short-term REM sleep deprivation can induce the expression of phospho-eIF2α protein which inhibit the synthesis of protein.