面神经断裂后大鼠面神经核区神经元凋亡和星形胶质细胞变化的实验研究

目的：研究面神经断裂后面神经核区神经元凋亡基因bcl-2,bax和星形胶质细胞变化及其意义。方法：大鼠面神经离断后，采用免疫组化的方法，通过图像分析和对面神经核区神经元bcl-2,bax的表达和星形胶质细胞变化进行定量分析。结果：面神经断裂后15d面神经核内神经元出现凋亡高峰，bcl-2/bax在面神经断裂后15d达最低，与正常对照组相差显著（P＜0．01），GFAP阳性细胞达最多，细胞着色最明显，与正常对照组相差显著（P＜0．01），结论：bcl-2和bax可能在面神经元凋亡过程中发挥重要作用；星形胶质细胞反应与面神经元的损伤和修复关系密切。

Changes of astrocytes and apoptosis of neurons in facial nerve nucleus after facial nerve transection in rats

Objective To observe the changes of astrocytes and expressions of bcl 2 and bax in neuron apoptosis in facial nerve nucleus after facial nerve transection in rats Methods A total of 72 rats were equally divided into normal control, and facial neurotmesis groups. Six rats were killed 3,7,15,21,30 and 60 d after transection respectively and same amount of rats were killed in same time interval in the control group. Brain samples were taken from the aboue mentioned rats and the facial neuron apoptosis was detected with TUNEL, and expressions of bcl 2 and bax and changes of GFAP in the astrocytes of facial nerve nucleus were studied with immunohistochemical methods and image analyses separately Results The apoptotic peak of facial neurons and remarkable expression of bcl 2 and bax appeared in 15 d after the facial neurotmesis, while the expression ratio of bcl 2/bax were the lowest Meantime, the reaction of the astrocytes(GFAP)was remarkable, too All the changes were statisfically significantly compared with the control groups ( P <0 01) Conclusion bcl 2 and bax have important effect on the apoptosis of facial neurons, whereas the reaction of astrocytes is significantly correlated with the damage and repair of the facial neurons after the facial neurotmesis