睡眠剥夺对大鼠海马锥体细胞超微结构影响

Effect of paradoxical sleep deprivation on ultrastructure of pyramidal cell of hippocampus of rats

目的研究异相睡眠剥夺对大鼠海马CA1区锥体细胞形态、超微结构及线粒体的损伤作用,以阐明其介导的海马神经元凋亡机制。方法选用成年SD大鼠随机分组,采用多平台水环境法制备睡眠剥夺模型,以尼氏(Nissl)染色法光镜下观察神经元形态,并用透射电镜进一步观察海马神经元超微结构的变化,采用免疫组织化学法测定细胞色素C的水平。结果睡眠剥夺造成海马CA1区细胞数量减少,细胞排列松散,出现大量空泡。透射电镜检测显示,海马CA1区,神经元轴突水肿明显,内质网扩张,线粒体肿胀,嵴结构模糊、紊乱,线粒体数量减少,有的呈空泡样变。胞浆内细胞色素C水平明显增高。结论睡眠剥夺造成海马CA1区线粒体损伤,释放细胞色素C,从而介导了海马神经元的凋亡。

Objective To illustrate the mechanism of mitochondria-induced neuron apoptosis of hippocampus, the effect of paradoxical sleep deprivation on microstructure of pyramidal neurons and mitochondria of CA1 region of hippocampus was studied. Methods Adult SD rats were chosen and random grouping was applied, Sleeping deprivation model was provided by modified multiple platform method. Nissl stain and light microscope were applied to observe the morphological changes of hippocampus, while TEM was used for observing the transformation of ultra-structure of hippocampus. The level of CytC expression was assessed by immunohistochemical method. Results The quantity of the cell in hippocampus CA1 region decreased after sleep deprivation, while cell sequence was loosen and a number of vacuoles appeared. Under the TEM observation, endoplasmic reticulum was extended. And there were obvious dropsy of neurite and mitochondria swelling. Cristae structure was getting disordered while the quantity of mitochondria decreased and vacuole sample transform appeared. The level of CytC in endochylema was growing up. Conclusion Sleep deprivation mediates the apoptosis of hippocampus neuron by damaging the cell of hippocampus CA1 region, and releasing the CytC.