【摘要】 为探讨慢性给予应激水平糖皮质激素对大鼠海马的影响,在实验组大鼠饮用水中加入皮质醇,使动物皮质醇吸收量达每日10mg/kg,从而引起与应激动物相同的皮质醇水平,共21d,然后用免疫组织化学和免疫印迹法观察海马内caspase-3、synap-tophysin(Syn)和neurogranin(Ng)表达的变化。结果显示:(1)实验组大鼠海马结构中可见较多细胞出现核固缩的病理改变,但未见或偶见极个别caspase-3免疫反应阳性细胞;(2)与正常组Syn表达水平(1.2197±0.3443)和Ng表达水平(1.9330±0.3450)相比,实验组大鼠海马结构中Syn和Ng的表达明显减少(P<0.05),其表达水平分别为0.5512±0.0540和1.3375±0.3317。上述结果表明慢性给予应激水平的糖皮质激素可损伤海马功能,引起不依赖caspase-3的海马神经细胞退变、使海马突触数量减少以及改变海马突触效能可能是其作用的部分机制。更多还原

【Abstract】 To explore the effect of chronic stressed level of glucocorticoid on hippocampus, the rats in treatment group were treated with 10 mg/(kg·d) of hydrocortisone (cortisol) in drinking water for 21 days. Then the expressions of caspase-3, synaptophysin (Syn) and neurogranin (Ng) in the hippocampus were observed by both immunohistochemistry and Western blotting. The results are as follows:(1)Nuclear pyknosis was seen in many cells of the hippocampus, but caspase-3 immunoreactive positive cells were not seen or just occasionally seen in the treatment group. (2) Western blot showed that the expression levels of Syn (0.5512±0.0540) and Ng (1.3375±0.3317) in the treatment group were significantly lower than those of the control group (P<0.05), which were 1.2197±0.3443 and 1.9330±0.3450, respectively. The results indicate that administration with chronic stressed level of glucocorticoid may affect the functions of hippocampus. caspase-3-independent degeneration of neurons and changes in synaptic efficacy and number in hippocampus may be involved in this process.更多还原