面神经损伤后神经元中BCL-2、P53表达的实验研究

Expressions of BCL-2 and P53 in neurons following facial nerve injury

目的研究大鼠面神经总干压榨伤及切断伤后,BCL-2、P53在其神经元中的表达。方法将35只SD大鼠随机分为三组:组I右侧面神经总干压榨伤,组II为同体左侧面神经总干切断伤,组Ⅲ为正常对照侧。用HE染色的方法观测术后各期面神经元的形态学变化,用二步免疫组化法检测面神经元内BCL-2、P53蛋白的表达。结果面神经总干压榨伤后,其神经元未发生死亡,而总干切断伤会引起神经元死亡,面神经干切断1w后BCL-2、P53蛋白表达开始增强,3w时达到高峰,且切断后神经元数与BCL-2,P53的表达有明显相关性。结论BCL-2、P53蛋白参与面神经总干切断后诱导神经元凋亡过程的调控,BCL-2,P53的表达变化决定面神经死亡。

Objective To investigate the expressions of BCL - 2 and P53 in neurons after facial nerve resection or crush at its stylomastoid foramen. Methods The left facial nerves in 25 rats were resected at its stylomastoid foramen （ group Ⅱ ） while the right facial nerves were crushed （ group Ⅰ ）. Ten intact rats were served as control （ group Ⅲ ）. The morphology of facial neurons was examined by HE staining. The expressions of BCL - 2 and P53 protein in facial neurons were also analyzed by immunostaining. Results The death of motoneurons were induced by facial nerve resection, whereas no death of motoneurons was observed in facial nerve crushed group. The expressions of BCL - 2 and P53 in neurons began to increase one week after the surgery and peaked at three weeks after the surgery. There was an obvious correlation between the expressions of BCL - 2,P53 and the number of motoneurons following facial nerve resection. Conclusion The induction of motoneuron apoptosis by facial nerve resection may be related with the expressions of BCL - 2 and P53.