慢性应激对大鼠海马CA3区锥体细胞形态结构的效应

Effects of chronic stress on morphology and structure of rat hippocampal CA3 pyramidal neurons

目的 探讨慢性应激对大鼠海马CA3区锥体细胞形态结构的效应。方法 将 2 6只雄性Sprague Dawley大鼠随机分为对照组和应激组 ,每组 13只。采用尼氏 (Nissl)染色法、高尔基 (Golgi)镀染法和透射电镜技术 ,观察慢性强迫游泳应激对大鼠海马CA3区锥体细胞形态结构的效应。结果应激组大鼠海马CA3区锥体细胞数 (35 1± 3 9)较对照组 (38 7± 3 5 )明显减少 (P <0 0 5 ) ;顶树突的总长度为 (15 5 7± 33 3) μm ,较对照组 (195 6± 34 6 ) μm明显缩短 (P <0 0 5 )。应激组大鼠海马CA3区锥体细胞出现超微结构的改变 ,包括细胞固缩、体积缩小、核膜皱缩、线粒体变性和粗面内质网模糊不清。结论 慢性应激可引起海马CA3区锥体细胞形态和微细结构的改变及细胞丧失。

Objective To explore the effects of chronic forced-swimming on morphology and structure of rat hippocampal CA3 pyramidal neurons. Methods Twenty-six male Sprague-Dawley rats were randomly divided into stress group and control group, 13 rats in each group. The effect of chronic stress on morphology and structure of rat hippocampal CA3 pyramidal neurons was detected with Nissl staining, Golgi staining and electron microscope. Results The number of hippocampal CA3 pyramidal neurons in stress group (35.1±3.9) was significantly less than that in control group (38.7±3.5) ,P<0.05. The total length of apical dendrite in stress group (55.7±33.3) μm was significantly shorter than that in control group (195.6±34.6 ) μm ,P<0.05. The ultrastructural changes, including the solid-shrink of whole cell, reduction of cell volume, wrinkle of cell membrane, degeneration of mitochondria and illegibility of the rough endoplasmic reticulum, were observed in hippocampal CA3 pyramidal neurons in chronic stress rats. Conclusion It is suggested that chronic stress can make changes of morphology and microstructure and cell loss in hippocampal CA3 pyramidal neuron.