大鼠面神经切断及修复后面神经核内胆碱乙酰转移酶的变化

CHANGES OF CHOLINE ACETYLTRANSFERASE IN THE RAT FACIAL NUCLEUS FOLLOWING THE FACIAL NERVE TRANSECTION AND REPAIR

为了研究面神经核胆碱乙酰转移酶在神经损伤及修复后的动态变化 ,用免疫组织化学方法 ,观察了成年大鼠面神经外周切断和即刻端端吻合后面神经核胆碱乙酰转移酶阳性神经元的数量和免疫反应强度的时程变化。结果证明 ,面神经切断后 ,损伤侧面神经核胆碱乙酰转移酶阳性神经元的数量和免疫反应强度均明显下降 ,术后第 7d下降至最低。面神经切断后立即行端端吻合 ,术后 7d内手术侧面神经核胆碱乙酰转移酶阳性神经元的数量和免疫反应强度的下降规律与面神经单纯切断组相同。面神经吻合后 ,术侧面神经核胆碱乙酰转移酶阳性神经元的数量和免疫反应强度的回升最早出现在吻合后第 14 d,术后 3 5 d手术侧面神经核胆碱乙酰转移酶阳性神经元的数量恢复至正常。上述结果提示 ,面神经吻合并不能阻止损伤侧面神经核胆碱乙酰转移酶免疫阳性产物的下降 ;伴随着面神经再支配的发生 。

To examine the changes of choline acetyltransferase (ChAT) in facial nucleus following the facial nerve injury and repair, we analyzed the changes of the number of ChAT positive neurons and the intensity of immunostaining in adult rat facial nucleus following peripheral nerve transection and immediate end to end anastomosis by immunohistochemical methods. A permant transection of facial nerve resulted in a striking reduction in both the number of ChAT positive neurons and the intensity of immunoreaction in facial nucleus ipsilateral to the operation, the peak of the reduction was reached at 7 day post operation. The patterns of reduction in both the number of ChAT positive neurons and the intensity of immunoreaction following an immediate end to end anastomosis within 7 days post operation were similar to that of transection group. These values on the operative side began to increase at the time point 14 day post anastomosis. At 35 day post anastomosis, the number of ChAT positive neurons on the operative side recovered to normal level. These results indicated that the immediate end to end anastomosis after facial nerve transection could not prevent the reduction in both the number of ChAT positive neurons and the intensity of immunoreaction. The reinnervation of facial nerve was accompanied with the return of axotomy induced decrease of ChAT immunoreactivity within facial nucleus.